Another Idea:
For race cars with multiple paint jobs such as the GT500 Super GT cars & NASCARs. I think it would be nice if PD had it so you could just choose one certain race car and then pick your livery like how you would pick a color for a normal car.
Examples:
1999 Toyota Supra GT500 (JGTC); you could pick either of these: Castrom Tom's, Denso Sard, or the Cerumo One livery.
1998 Ford Escort Rally Car (WRC); the options could include either: Vavoline Ford Livery, Infrogames V-Rally livery, or the Respol livery.
1993 Nissan Skyline Race Car; Livery options: Calsonic, BP, or Winfield Racing livery.