[Suggestion]
Livery Editor: Undo/Redo
Undo/redo is a standard tool in just about every creative application I can think of. In both Forza Motorsport and Horizon, it is far too easy to make a selection error with the cumbersome UI, costing you hours and hours worth of work that is unrecoverable.
While some other applications do bank a large number of your consecutive actions that are available for you to undo as necessary, here for our purposes we could cap banked actions at a more conservative number, like 10. That, I think, would be sufficient for most livery creators to correct any ruinous errors.