One of the things I would love to do in this game is to be able to use assets already in game and save them so I can use them across a whole model line, such as a brand logo or a car name badge.
I know I can make a mod for a badge but something like the decal editor in Forza being implemented in game would be a huge boon for the playability of this game for more casual players. Just being able to save several layers of decals into a single larger group would really streamline the car design editor a lot.