I'd like to see Custom Races improved, and especially the requirement to own multiple copies of the same car just to be able to run different liveries.
At the moment, one can race against a full field of the same car (with the same livery), so creating 'temporary dupes' is clearly not the problem. But if you want these to have custom liveries, they need to be selected from the garage with the livery already applied. Being able to create temporary duplicates and apply different liveries would make Custom Races much easier/quicker to set up.
-
I also thought about one-click car upgrades, and figured that the Tuning shop could have car-specific tuning packs, like Manthey for the Porsche 911. That would be pretty cool, and much easier than manually adding parts and then tuning the car.