diff --git a/src/common/input.h b/src/common/input.h
index eaee0bdea..0b92449bc 100644
--- a/src/common/input.h
+++ b/src/common/input.h
@@ -266,11 +266,9 @@ class OutputDevice {
 public:
     virtual ~OutputDevice() = default;
 
-    virtual void SetLED([[maybe_unused]] LedStatus led_status) {
-        return;
-    }
+    virtual void SetLED([[maybe_unused]] const LedStatus& led_status) {}
 
-    virtual VibrationError SetVibration([[maybe_unused]] VibrationStatus vibration_status) {
+    virtual VibrationError SetVibration([[maybe_unused]] const VibrationStatus& vibration_status) {
         return VibrationError::NotSupported;
     }
 
diff --git a/src/input_common/drivers/gc_adapter.cpp b/src/input_common/drivers/gc_adapter.cpp
index 8b6574223..7ab4540a8 100644
--- a/src/input_common/drivers/gc_adapter.cpp
+++ b/src/input_common/drivers/gc_adapter.cpp
@@ -69,7 +69,7 @@ private:
     libusb_device_handle* handle{};
 };
 
-GCAdapter::GCAdapter(const std::string& input_engine_) : InputEngine(input_engine_) {
+GCAdapter::GCAdapter(std::string input_engine_) : InputEngine(std::move(input_engine_)) {
     if (usb_adapter_handle) {
         return;
     }
@@ -325,8 +325,8 @@ bool GCAdapter::GetGCEndpoint(libusb_device* device) {
     return true;
 }
 
-Common::Input::VibrationError GCAdapter::SetRumble(const PadIdentifier& identifier,
-                                                   const Common::Input::VibrationStatus vibration) {
+Common::Input::VibrationError GCAdapter::SetRumble(
+    const PadIdentifier& identifier, const Common::Input::VibrationStatus& vibration) {
     const auto mean_amplitude = (vibration.low_amplitude + vibration.high_amplitude) * 0.5f;
     const auto processed_amplitude =
         static_cast<u8>((mean_amplitude + std::pow(mean_amplitude, 0.3f)) * 0.5f * 0x8);
diff --git a/src/input_common/drivers/gc_adapter.h b/src/input_common/drivers/gc_adapter.h
index 8dc51d2e5..7ce1912a3 100644
--- a/src/input_common/drivers/gc_adapter.h
+++ b/src/input_common/drivers/gc_adapter.h
@@ -22,13 +22,13 @@ namespace InputCommon {
 class LibUSBContext;
 class LibUSBDeviceHandle;
 
-class GCAdapter : public InputCommon::InputEngine {
+class GCAdapter : public InputEngine {
 public:
-    explicit GCAdapter(const std::string& input_engine_);
-    ~GCAdapter();
+    explicit GCAdapter(std::string input_engine_);
+    ~GCAdapter() override;
 
     Common::Input::VibrationError SetRumble(
-        const PadIdentifier& identifier, const Common::Input::VibrationStatus vibration) override;
+        const PadIdentifier& identifier, const Common::Input::VibrationStatus& vibration) override;
 
     /// Used for automapping features
     std::vector<Common::ParamPackage> GetInputDevices() const override;
diff --git a/src/input_common/drivers/keyboard.cpp b/src/input_common/drivers/keyboard.cpp
index 23b0c0ccf..4c1e5bbec 100644
--- a/src/input_common/drivers/keyboard.cpp
+++ b/src/input_common/drivers/keyboard.cpp
@@ -24,7 +24,7 @@ constexpr PadIdentifier keyboard_modifier_identifier = {
     .pad = 1,
 };
 
-Keyboard::Keyboard(const std::string& input_engine_) : InputEngine(input_engine_) {
+Keyboard::Keyboard(std::string input_engine_) : InputEngine(std::move(input_engine_)) {
     // Keyboard is broken into 3 diferent sets:
     // key: Unfiltered intended for controllers.
     // keyboard_key: Allows only Settings::NativeKeyboard::Keys intended for keyboard emulation.
diff --git a/src/input_common/drivers/keyboard.h b/src/input_common/drivers/keyboard.h
index ad123b136..3856c882c 100644
--- a/src/input_common/drivers/keyboard.h
+++ b/src/input_common/drivers/keyboard.h
@@ -12,9 +12,9 @@ namespace InputCommon {
  * A button device factory representing a keyboard. It receives keyboard events and forward them
  * to all button devices it created.
  */
-class Keyboard final : public InputCommon::InputEngine {
+class Keyboard final : public InputEngine {
 public:
-    explicit Keyboard(const std::string& input_engine_);
+    explicit Keyboard(std::string input_engine_);
 
     /**
      * Sets the status of all buttons bound with the key to pressed
diff --git a/src/input_common/drivers/mouse.cpp b/src/input_common/drivers/mouse.cpp
index 752118e97..aa69216c8 100644
--- a/src/input_common/drivers/mouse.cpp
+++ b/src/input_common/drivers/mouse.cpp
@@ -24,7 +24,7 @@ constexpr PadIdentifier identifier = {
     .pad = 0,
 };
 
-Mouse::Mouse(const std::string& input_engine_) : InputEngine(input_engine_) {
+Mouse::Mouse(std::string input_engine_) : InputEngine(std::move(input_engine_)) {
     PreSetController(identifier);
     PreSetAxis(identifier, mouse_axis_x);
     PreSetAxis(identifier, mouse_axis_y);
diff --git a/src/input_common/drivers/mouse.h b/src/input_common/drivers/mouse.h
index 4a1fd2fd9..040446178 100644
--- a/src/input_common/drivers/mouse.h
+++ b/src/input_common/drivers/mouse.h
@@ -27,9 +27,9 @@ enum class MouseButton {
  * A button device factory representing a keyboard. It receives keyboard events and forward them
  * to all button devices it created.
  */
-class Mouse final : public InputCommon::InputEngine {
+class Mouse final : public InputEngine {
 public:
-    explicit Mouse(const std::string& input_engine_);
+    explicit Mouse(std::string input_engine_);
 
     /**
      * Signals that mouse has moved.
diff --git a/src/input_common/drivers/sdl_driver.cpp b/src/input_common/drivers/sdl_driver.cpp
index 1052ed394..e33a5ff31 100644
--- a/src/input_common/drivers/sdl_driver.cpp
+++ b/src/input_common/drivers/sdl_driver.cpp
@@ -88,7 +88,7 @@ public:
         return true;
     }
 
-    BasicMotion GetMotion() {
+    const BasicMotion& GetMotion() const {
         return motion;
     }
 
@@ -367,7 +367,7 @@ void SDLDriver::HandleGameControllerEvent(const SDL_Event& event) {
             if (joystick->UpdateMotion(event.csensor)) {
                 const PadIdentifier identifier = joystick->GetPadIdentifier();
                 SetMotion(identifier, 0, joystick->GetMotion());
-            };
+            }
         }
         break;
     }
@@ -387,7 +387,7 @@ void SDLDriver::CloseJoysticks() {
     joystick_map.clear();
 }
 
-SDLDriver::SDLDriver(const std::string& input_engine_) : InputEngine(input_engine_) {
+SDLDriver::SDLDriver(std::string input_engine_) : InputEngine(std::move(input_engine_)) {
     if (!Settings::values.enable_raw_input) {
         // Disable raw input. When enabled this setting causes SDL to die when a web applet opens
         SDL_SetHint(SDL_HINT_JOYSTICK_RAWINPUT, "0");
@@ -491,8 +491,9 @@ std::vector<Common::ParamPackage> SDLDriver::GetInputDevices() const {
     }
     return devices;
 }
-Common::Input::VibrationError SDLDriver::SetRumble(const PadIdentifier& identifier,
-                                                   const Common::Input::VibrationStatus vibration) {
+
+Common::Input::VibrationError SDLDriver::SetRumble(
+    const PadIdentifier& identifier, const Common::Input::VibrationStatus& vibration) {
     const auto joystick =
         GetSDLJoystickByGUID(identifier.guid.Format(), static_cast<int>(identifier.port));
     const auto process_amplitude_exp = [](f32 amplitude, f32 factor) {
@@ -526,6 +527,7 @@ Common::Input::VibrationError SDLDriver::SetRumble(const PadIdentifier& identifi
 
     return Common::Input::VibrationError::None;
 }
+
 Common::ParamPackage SDLDriver::BuildAnalogParamPackageForButton(int port, std::string guid,
                                                                  s32 axis, float value) const {
     Common::ParamPackage params{};
diff --git a/src/input_common/drivers/sdl_driver.h b/src/input_common/drivers/sdl_driver.h
index d03ff4b84..e9a5d2e26 100644
--- a/src/input_common/drivers/sdl_driver.h
+++ b/src/input_common/drivers/sdl_driver.h
@@ -19,19 +19,19 @@ using SDL_GameController = struct _SDL_GameController;
 using SDL_Joystick = struct _SDL_Joystick;
 using SDL_JoystickID = s32;
 
+namespace InputCommon {
+
+class SDLJoystick;
+
 using ButtonBindings =
     std::array<std::pair<Settings::NativeButton::Values, SDL_GameControllerButton>, 17>;
 using ZButtonBindings =
     std::array<std::pair<Settings::NativeButton::Values, SDL_GameControllerAxis>, 2>;
 
-namespace InputCommon {
-
-class SDLJoystick;
-
-class SDLDriver : public InputCommon::InputEngine {
+class SDLDriver : public InputEngine {
 public:
     /// Initializes and registers SDL device factories
-    SDLDriver(const std::string& input_engine_);
+    explicit SDLDriver(std::string input_engine_);
 
     /// Unregisters SDL device factories and shut them down.
     ~SDLDriver() override;
@@ -59,7 +59,7 @@ public:
     u8 GetHatButtonId(const std::string& direction_name) const override;
 
     Common::Input::VibrationError SetRumble(
-        const PadIdentifier& identifier, const Common::Input::VibrationStatus vibration) override;
+        const PadIdentifier& identifier, const Common::Input::VibrationStatus& vibration) override;
 
 private:
     void InitJoystick(int joystick_index);
diff --git a/src/input_common/drivers/tas_input.cpp b/src/input_common/drivers/tas_input.cpp
index 2094c1feb..5bdd5dac3 100644
--- a/src/input_common/drivers/tas_input.cpp
+++ b/src/input_common/drivers/tas_input.cpp
@@ -46,7 +46,7 @@ constexpr std::array<std::pair<std::string_view, TasButton>, 20> text_to_tas_but
     {"KEY_ZR", TasButton::TRIGGER_ZR},
 };
 
-Tas::Tas(const std::string& input_engine_) : InputCommon::InputEngine(input_engine_) {
+Tas::Tas(std::string input_engine_) : InputEngine(std::move(input_engine_)) {
     for (size_t player_index = 0; player_index < PLAYER_NUMBER; player_index++) {
         PadIdentifier identifier{
             .guid = Common::UUID{},
diff --git a/src/input_common/drivers/tas_input.h b/src/input_common/drivers/tas_input.h
index 3996fe3a8..4b4e6c417 100644
--- a/src/input_common/drivers/tas_input.h
+++ b/src/input_common/drivers/tas_input.h
@@ -81,10 +81,10 @@ enum class TasState {
     Stopped,
 };
 
-class Tas final : public InputCommon::InputEngine {
+class Tas final : public InputEngine {
 public:
-    explicit Tas(const std::string& input_engine_);
-    ~Tas();
+    explicit Tas(std::string input_engine_);
+    ~Tas() override;
 
     /**
      * Changes the input status that will be stored in each frame
diff --git a/src/input_common/drivers/touch_screen.cpp b/src/input_common/drivers/touch_screen.cpp
index 45b3086f6..880781825 100644
--- a/src/input_common/drivers/touch_screen.cpp
+++ b/src/input_common/drivers/touch_screen.cpp
@@ -13,7 +13,7 @@ constexpr PadIdentifier identifier = {
     .pad = 0,
 };
 
-TouchScreen::TouchScreen(const std::string& input_engine_) : InputEngine(input_engine_) {
+TouchScreen::TouchScreen(std::string input_engine_) : InputEngine(std::move(input_engine_)) {
     PreSetController(identifier);
 }
 
diff --git a/src/input_common/drivers/touch_screen.h b/src/input_common/drivers/touch_screen.h
index 25c11e8bf..bf395c40b 100644
--- a/src/input_common/drivers/touch_screen.h
+++ b/src/input_common/drivers/touch_screen.h
@@ -12,9 +12,9 @@ namespace InputCommon {
  * A button device factory representing a keyboard. It receives keyboard events and forward them
  * to all button devices it created.
  */
-class TouchScreen final : public InputCommon::InputEngine {
+class TouchScreen final : public InputEngine {
 public:
-    explicit TouchScreen(const std::string& input_engine_);
+    explicit TouchScreen(std::string input_engine_);
 
     /**
      * Signals that mouse has moved.
diff --git a/src/input_common/drivers/udp_client.cpp b/src/input_common/drivers/udp_client.cpp
index fdee0f2d5..4ab991a7d 100644
--- a/src/input_common/drivers/udp_client.cpp
+++ b/src/input_common/drivers/udp_client.cpp
@@ -136,7 +136,7 @@ static void SocketLoop(Socket* socket) {
     socket->Loop();
 }
 
-UDPClient::UDPClient(const std::string& input_engine_) : InputEngine(input_engine_) {
+UDPClient::UDPClient(std::string input_engine_) : InputEngine(std::move(input_engine_)) {
     LOG_INFO(Input, "Udp Initialization started");
     ReloadSockets();
 }
diff --git a/src/input_common/drivers/udp_client.h b/src/input_common/drivers/udp_client.h
index 5d483f26b..1adc947c4 100644
--- a/src/input_common/drivers/udp_client.h
+++ b/src/input_common/drivers/udp_client.h
@@ -49,10 +49,10 @@ struct DeviceStatus {
  * A button device factory representing a keyboard. It receives keyboard events and forward them
  * to all button devices it created.
  */
-class UDPClient final : public InputCommon::InputEngine {
+class UDPClient final : public InputEngine {
 public:
-    explicit UDPClient(const std::string& input_engine_);
-    ~UDPClient();
+    explicit UDPClient(std::string input_engine_);
+    ~UDPClient() override;
 
     void ReloadSockets();
 
diff --git a/src/input_common/input_engine.cpp b/src/input_common/input_engine.cpp
index 2b2105376..9c17ca4f7 100644
--- a/src/input_common/input_engine.cpp
+++ b/src/input_common/input_engine.cpp
@@ -10,41 +10,31 @@ namespace InputCommon {
 
 void InputEngine::PreSetController(const PadIdentifier& identifier) {
     std::lock_guard lock{mutex};
-    if (!controller_list.contains(identifier)) {
-        controller_list.insert_or_assign(identifier, ControllerData{});
-    }
+    controller_list.try_emplace(identifier);
 }
 
 void InputEngine::PreSetButton(const PadIdentifier& identifier, int button) {
     std::lock_guard lock{mutex};
     ControllerData& controller = controller_list.at(identifier);
-    if (!controller.buttons.contains(button)) {
-        controller.buttons.insert_or_assign(button, false);
-    }
+    controller.buttons.try_emplace(button, false);
 }
 
 void InputEngine::PreSetHatButton(const PadIdentifier& identifier, int button) {
     std::lock_guard lock{mutex};
     ControllerData& controller = controller_list.at(identifier);
-    if (!controller.hat_buttons.contains(button)) {
-        controller.hat_buttons.insert_or_assign(button, u8{0});
-    }
+    controller.hat_buttons.try_emplace(button, u8{0});
 }
 
 void InputEngine::PreSetAxis(const PadIdentifier& identifier, int axis) {
     std::lock_guard lock{mutex};
     ControllerData& controller = controller_list.at(identifier);
-    if (!controller.axes.contains(axis)) {
-        controller.axes.insert_or_assign(axis, 0.0f);
-    }
+    controller.axes.try_emplace(axis, 0.0f);
 }
 
 void InputEngine::PreSetMotion(const PadIdentifier& identifier, int motion) {
     std::lock_guard lock{mutex};
     ControllerData& controller = controller_list.at(identifier);
-    if (!controller.motions.contains(motion)) {
-        controller.motions.insert_or_assign(motion, BasicMotion{});
-    }
+    controller.motions.try_emplace(motion);
 }
 
 void InputEngine::SetButton(const PadIdentifier& identifier, int button, bool value) {
@@ -91,7 +81,7 @@ void InputEngine::SetBattery(const PadIdentifier& identifier, BatteryLevel value
     TriggerOnBatteryChange(identifier, value);
 }
 
-void InputEngine::SetMotion(const PadIdentifier& identifier, int motion, BasicMotion value) {
+void InputEngine::SetMotion(const PadIdentifier& identifier, int motion, const BasicMotion& value) {
     {
         std::lock_guard lock{mutex};
         ControllerData& controller = controller_list.at(identifier);
@@ -104,85 +94,93 @@ void InputEngine::SetMotion(const PadIdentifier& identifier, int motion, BasicMo
 
 bool InputEngine::GetButton(const PadIdentifier& identifier, int button) const {
     std::lock_guard lock{mutex};
-    if (!controller_list.contains(identifier)) {
+    const auto controller_iter = controller_list.find(identifier);
+    if (controller_iter == controller_list.cend()) {
         LOG_ERROR(Input, "Invalid identifier guid={}, pad={}, port={}", identifier.guid.Format(),
                   identifier.pad, identifier.port);
         return false;
     }
-    ControllerData controller = controller_list.at(identifier);
-    if (!controller.buttons.contains(button)) {
+    const ControllerData& controller = controller_iter->second;
+    const auto button_iter = controller.buttons.find(button);
+    if (button_iter == controller.buttons.cend()) {
         LOG_ERROR(Input, "Invalid button {}", button);
         return false;
     }
-    return controller.buttons.at(button);
+    return button_iter->second;
 }
 
 bool InputEngine::GetHatButton(const PadIdentifier& identifier, int button, u8 direction) const {
     std::lock_guard lock{mutex};
-    if (!controller_list.contains(identifier)) {
+    const auto controller_iter = controller_list.find(identifier);
+    if (controller_iter == controller_list.cend()) {
         LOG_ERROR(Input, "Invalid identifier guid={}, pad={}, port={}", identifier.guid.Format(),
                   identifier.pad, identifier.port);
         return false;
     }
-    ControllerData controller = controller_list.at(identifier);
-    if (!controller.hat_buttons.contains(button)) {
+    const ControllerData& controller = controller_iter->second;
+    const auto hat_iter = controller.hat_buttons.find(button);
+    if (hat_iter == controller.hat_buttons.cend()) {
         LOG_ERROR(Input, "Invalid hat button {}", button);
         return false;
     }
-    return (controller.hat_buttons.at(button) & direction) != 0;
+    return (hat_iter->second & direction) != 0;
 }
 
 f32 InputEngine::GetAxis(const PadIdentifier& identifier, int axis) const {
     std::lock_guard lock{mutex};
-    if (!controller_list.contains(identifier)) {
+    const auto controller_iter = controller_list.find(identifier);
+    if (controller_iter == controller_list.cend()) {
         LOG_ERROR(Input, "Invalid identifier guid={}, pad={}, port={}", identifier.guid.Format(),
                   identifier.pad, identifier.port);
         return 0.0f;
     }
-    ControllerData controller = controller_list.at(identifier);
-    if (!controller.axes.contains(axis)) {
+    const ControllerData& controller = controller_iter->second;
+    const auto axis_iter = controller.axes.find(axis);
+    if (axis_iter == controller.axes.cend()) {
         LOG_ERROR(Input, "Invalid axis {}", axis);
         return 0.0f;
     }
-    return controller.axes.at(axis);
+    return axis_iter->second;
 }
 
 BatteryLevel InputEngine::GetBattery(const PadIdentifier& identifier) const {
     std::lock_guard lock{mutex};
-    if (!controller_list.contains(identifier)) {
+    const auto controller_iter = controller_list.find(identifier);
+    if (controller_iter == controller_list.cend()) {
         LOG_ERROR(Input, "Invalid identifier guid={}, pad={}, port={}", identifier.guid.Format(),
                   identifier.pad, identifier.port);
         return BatteryLevel::Charging;
     }
-    ControllerData controller = controller_list.at(identifier);
+    const ControllerData& controller = controller_iter->second;
     return controller.battery;
 }
 
 BasicMotion InputEngine::GetMotion(const PadIdentifier& identifier, int motion) const {
     std::lock_guard lock{mutex};
-    if (!controller_list.contains(identifier)) {
+    const auto controller_iter = controller_list.find(identifier);
+    if (controller_iter == controller_list.cend()) {
         LOG_ERROR(Input, "Invalid identifier guid={}, pad={}, port={}", identifier.guid.Format(),
                   identifier.pad, identifier.port);
         return {};
     }
-    ControllerData controller = controller_list.at(identifier);
+    const ControllerData& controller = controller_iter->second;
     return controller.motions.at(motion);
 }
 
 void InputEngine::ResetButtonState() {
-    for (std::pair<PadIdentifier, ControllerData> controller : controller_list) {
-        for (std::pair<int, bool> button : controller.second.buttons) {
+    for (const auto& controller : controller_list) {
+        for (const auto& button : controller.second.buttons) {
             SetButton(controller.first, button.first, false);
         }
-        for (std::pair<int, bool> button : controller.second.hat_buttons) {
+        for (const auto& button : controller.second.hat_buttons) {
             SetHatButton(controller.first, button.first, false);
         }
     }
 }
 
 void InputEngine::ResetAnalogState() {
-    for (std::pair<PadIdentifier, ControllerData> controller : controller_list) {
-        for (std::pair<int, float> axis : controller.second.axes) {
+    for (const auto& controller : controller_list) {
+        for (const auto& axis : controller.second.axes) {
             SetAxis(controller.first, axis.first, 0.0);
         }
     }
@@ -190,7 +188,7 @@ void InputEngine::ResetAnalogState() {
 
 void InputEngine::TriggerOnButtonChange(const PadIdentifier& identifier, int button, bool value) {
     std::lock_guard lock{mutex_callback};
-    for (const std::pair<int, InputIdentifier> poller_pair : callback_list) {
+    for (const auto& poller_pair : callback_list) {
         const InputIdentifier& poller = poller_pair.second;
         if (!IsInputIdentifierEqual(poller, identifier, EngineInputType::Button, button)) {
             continue;
@@ -218,7 +216,7 @@ void InputEngine::TriggerOnButtonChange(const PadIdentifier& identifier, int but
 
 void InputEngine::TriggerOnHatButtonChange(const PadIdentifier& identifier, int button, u8 value) {
     std::lock_guard lock{mutex_callback};
-    for (const std::pair<int, InputIdentifier> poller_pair : callback_list) {
+    for (const auto& poller_pair : callback_list) {
         const InputIdentifier& poller = poller_pair.second;
         if (!IsInputIdentifierEqual(poller, identifier, EngineInputType::HatButton, button)) {
             continue;
@@ -247,7 +245,7 @@ void InputEngine::TriggerOnHatButtonChange(const PadIdentifier& identifier, int
 
 void InputEngine::TriggerOnAxisChange(const PadIdentifier& identifier, int axis, f32 value) {
     std::lock_guard lock{mutex_callback};
-    for (const std::pair<int, InputIdentifier> poller_pair : callback_list) {
+    for (const auto& poller_pair : callback_list) {
         const InputIdentifier& poller = poller_pair.second;
         if (!IsInputIdentifierEqual(poller, identifier, EngineInputType::Analog, axis)) {
             continue;
@@ -274,7 +272,7 @@ void InputEngine::TriggerOnAxisChange(const PadIdentifier& identifier, int axis,
 void InputEngine::TriggerOnBatteryChange(const PadIdentifier& identifier,
                                          [[maybe_unused]] BatteryLevel value) {
     std::lock_guard lock{mutex_callback};
-    for (const std::pair<int, InputIdentifier> poller_pair : callback_list) {
+    for (const auto& poller_pair : callback_list) {
         const InputIdentifier& poller = poller_pair.second;
         if (!IsInputIdentifierEqual(poller, identifier, EngineInputType::Battery, 0)) {
             continue;
@@ -286,9 +284,9 @@ void InputEngine::TriggerOnBatteryChange(const PadIdentifier& identifier,
 }
 
 void InputEngine::TriggerOnMotionChange(const PadIdentifier& identifier, int motion,
-                                        BasicMotion value) {
+                                        const BasicMotion& value) {
     std::lock_guard lock{mutex_callback};
-    for (const std::pair<int, InputIdentifier> poller_pair : callback_list) {
+    for (const auto& poller_pair : callback_list) {
         const InputIdentifier& poller = poller_pair.second;
         if (!IsInputIdentifierEqual(poller, identifier, EngineInputType::Motion, motion)) {
             continue;
@@ -342,7 +340,7 @@ const std::string& InputEngine::GetEngineName() const {
 
 int InputEngine::SetCallback(InputIdentifier input_identifier) {
     std::lock_guard lock{mutex_callback};
-    callback_list.insert_or_assign(last_callback_key, input_identifier);
+    callback_list.insert_or_assign(last_callback_key, std::move(input_identifier));
     return last_callback_key++;
 }
 
diff --git a/src/input_common/input_engine.h b/src/input_common/input_engine.h
index 02272b3f8..390581c94 100644
--- a/src/input_common/input_engine.h
+++ b/src/input_common/input_engine.h
@@ -23,15 +23,15 @@ struct PadIdentifier {
     friend constexpr bool operator==(const PadIdentifier&, const PadIdentifier&) = default;
 };
 
-// Basic motion data containing data from the sensors and a timestamp in microsecons
+// Basic motion data containing data from the sensors and a timestamp in microseconds
 struct BasicMotion {
-    float gyro_x;
-    float gyro_y;
-    float gyro_z;
-    float accel_x;
-    float accel_y;
-    float accel_z;
-    u64 delta_timestamp;
+    float gyro_x{};
+    float gyro_y{};
+    float gyro_z{};
+    float accel_x{};
+    float accel_y{};
+    float accel_z{};
+    u64 delta_timestamp{};
 };
 
 // Stages of a battery charge
@@ -102,9 +102,7 @@ struct InputIdentifier {
 
 class InputEngine {
 public:
-    explicit InputEngine(const std::string& input_engine_) : input_engine(input_engine_) {
-        callback_list.clear();
-    }
+    explicit InputEngine(std::string input_engine_) : input_engine{std::move(input_engine_)} {}
 
     virtual ~InputEngine() = default;
 
@@ -116,14 +114,12 @@ public:
 
     // Sets a led pattern for a controller
     virtual void SetLeds([[maybe_unused]] const PadIdentifier& identifier,
-                         [[maybe_unused]] const Common::Input::LedStatus led_status) {
-        return;
-    }
+                         [[maybe_unused]] const Common::Input::LedStatus& led_status) {}
 
     // Sets rumble to a controller
     virtual Common::Input::VibrationError SetRumble(
         [[maybe_unused]] const PadIdentifier& identifier,
-        [[maybe_unused]] const Common::Input::VibrationStatus vibration) {
+        [[maybe_unused]] const Common::Input::VibrationStatus& vibration) {
         return Common::Input::VibrationError::NotSupported;
     }
 
@@ -140,36 +136,36 @@ public:
     /// Used for automapping features
     virtual std::vector<Common::ParamPackage> GetInputDevices() const {
         return {};
-    };
+    }
 
     /// Retrieves the button mappings for the given device
-    virtual InputCommon::ButtonMapping GetButtonMappingForDevice(
+    virtual ButtonMapping GetButtonMappingForDevice(
         [[maybe_unused]] const Common::ParamPackage& params) {
         return {};
-    };
+    }
 
     /// Retrieves the analog mappings for the given device
-    virtual InputCommon::AnalogMapping GetAnalogMappingForDevice(
+    virtual AnalogMapping GetAnalogMappingForDevice(
         [[maybe_unused]] const Common::ParamPackage& params) {
         return {};
-    };
+    }
 
     /// Retrieves the motion mappings for the given device
-    virtual InputCommon::MotionMapping GetMotionMappingForDevice(
+    virtual MotionMapping GetMotionMappingForDevice(
         [[maybe_unused]] const Common::ParamPackage& params) {
         return {};
-    };
+    }
 
     /// Retrieves the name of the given input.
     virtual Common::Input::ButtonNames GetUIName(
         [[maybe_unused]] const Common::ParamPackage& params) const {
         return Common::Input::ButtonNames::Engine;
-    };
+    }
 
     /// Retrieves the index number of the given hat button direction
     virtual u8 GetHatButtonId([[maybe_unused]] const std::string& direction_name) const {
         return 0;
-    };
+    }
 
     void PreSetController(const PadIdentifier& identifier);
     void PreSetButton(const PadIdentifier& identifier, int button);
@@ -194,7 +190,7 @@ protected:
     void SetHatButton(const PadIdentifier& identifier, int button, u8 value);
     void SetAxis(const PadIdentifier& identifier, int axis, f32 value);
     void SetBattery(const PadIdentifier& identifier, BatteryLevel value);
-    void SetMotion(const PadIdentifier& identifier, int motion, BasicMotion value);
+    void SetMotion(const PadIdentifier& identifier, int motion, const BasicMotion& value);
 
     virtual std::string GetHatButtonName([[maybe_unused]] u8 direction_value) const {
         return "Unknown";
@@ -206,14 +202,15 @@ private:
         std::unordered_map<int, u8> hat_buttons;
         std::unordered_map<int, float> axes;
         std::unordered_map<int, BasicMotion> motions;
-        BatteryLevel battery;
+        BatteryLevel battery{};
     };
 
     void TriggerOnButtonChange(const PadIdentifier& identifier, int button, bool value);
     void TriggerOnHatButtonChange(const PadIdentifier& identifier, int button, u8 value);
-    void TriggerOnAxisChange(const PadIdentifier& identifier, int button, f32 value);
+    void TriggerOnAxisChange(const PadIdentifier& identifier, int axis, f32 value);
     void TriggerOnBatteryChange(const PadIdentifier& identifier, BatteryLevel value);
-    void TriggerOnMotionChange(const PadIdentifier& identifier, int motion, BasicMotion value);
+    void TriggerOnMotionChange(const PadIdentifier& identifier, int motion,
+                               const BasicMotion& value);
 
     bool IsInputIdentifierEqual(const InputIdentifier& input_identifier,
                                 const PadIdentifier& identifier, EngineInputType type,
diff --git a/src/input_common/input_poller.cpp b/src/input_common/input_poller.cpp
index 7e4eafded..c56d5e0c2 100644
--- a/src/input_common/input_poller.cpp
+++ b/src/input_common/input_poller.cpp
@@ -668,12 +668,12 @@ public:
     explicit OutputFromIdentifier(PadIdentifier identifier_, InputEngine* input_engine_)
         : identifier(identifier_), input_engine(input_engine_) {}
 
-    virtual void SetLED(Common::Input::LedStatus led_status) {
+    virtual void SetLED(const Common::Input::LedStatus& led_status) {
         input_engine->SetLeds(identifier, led_status);
     }
 
     virtual Common::Input::VibrationError SetVibration(
-        Common::Input::VibrationStatus vibration_status) {
+        const Common::Input::VibrationStatus& vibration_status) {
         return input_engine->SetRumble(identifier, vibration_status);
     }