I'd like cars mostly for storytelling purposes- like my wealthy family should be able to buy a ton of fancy cars or my poor family should drive a junker. I think cars in ts4 should work exactly like they did in 2 in that they just had the animation of sims getting into the car and the car pulling out of the driveway and fading away. Another reason I want cars is because garages are missing and are a big part of the design of most American homes. Fixing cars up/rebuilding them as a hobby, like the car from Freetime or the sims 3 store, would also be awesome.
I also saw an idea of having cars be able to take sims to new hidden lots, which I really like.
