I'd like there to be a feature where you can toggle viewing the body panels or not on a car. The idea is to see just the powertrain. suspension, and wheels. I think it'd be such a cool feature as it could show off a lot of the technical prowess of the game and show us in real time what's going on with the engine, transmission and suspension.
If you go into the part selector and click the "eye" buttons, it toggles the visibility of that part.