Very simple feature request:
Tobii eye tracker integration. In particular just the face panning to look around inside the car like Kinect once upon a time allowed in Forza.
The best example of implementation is how Tobii works with DCS World - where you can bind a toggle or push to track button on your preferred device rather than having head tracking always active - their app also allows for quick editing of settings.
A second example of implementation is how it works in MSFS - in my view a slightly inferior implementation with less ability to customise the behaviour but still very impressive when tuned correctly.
An alternative would just be to expose to us camera axis so that we can map them to virtual d-input joysticks (tobii + opentrack allows for output in d-input axis with plenty of tuning options).