Hi, I am an indie game developer.
I have already made a 2D online game where you can design your own vehicles:
There are 12 options of materials to be used in vehicle creation: Frames, Wheels, Engines, Shock absorbers, Chains, Angle locks, Angle shocks, Pneumatic shocks, Actuators, Wings, Turbines, Point settings
You can try the game here: www.dreamcarracing.com
I am now developing the 3D version of the game.
(Platforms: PC, Mac, Linux)
Dream Car Racing 3D has already been Greenlit on Steam.
Let me know: what do you think about this idea?
Here are some videos of different versions of the game: