This would have racing contests with AI drivers and tests where you would test cars and other things that would get you money with that money you could unlock better cars and parts which you could upgrade your cars to race with.
I'm disappointed, thought this'd be a thread about Aircraft Carriers, or a mode where you carry other vehicles, but it turns out it's a suggestion about the game's Career. Now that I think about it, a carrier mode would be great, you'd deliver cars, like in that scenario.