It would be nice if the controls had some way of identifying the function by feel. As I understand it US designers before WW2 came up with the idea of shaping the handles to approximate the things they control. So the lever that controlled the landing gear was shaped like a wheel, and the lever for flaps were shaped like flaps.

Of course there are limits to how far you can go with this. Shaping the handles like a physical object is simple. But how do you reference a non-physical concept with a shape? Is there a shape that describes 'radio frequency' or 'GPS waypoint 03'.

Then again how many controls are really vital. I like simple vehicles where start, stop, and steer, are pretty much all you need because that is all that is really important. One of the reasons I like trucks is that you can, last time I checked, still get a vehicle with manual windows and locks.

As attractive as marking switches seems I'm leery about marking things as special because it is easy to imagine a situation where just about any control might be vitally important. If I mark all the switches then they are all special and if all are special then none of them are.

Seems to me that the what is needed is training and regular refresh training to make the location of the switches instinctual and automatic. You could make it a habit to physically manipulate all the switches when you get in so you are getting regular refreshing and checking switch function. Pilots have done this from day-one. Checklists and function tests make sure you and the machine are ready to fly.

I don't see why this wouldn't work for motor vehicles.