Haven't seen that busty Avatar in a while!
But back on topic, I'll admit that the Fiat Coupe (I forgot what it's called) kind of looks much different with a spoiler. I think of that car as being a 2-door that looks more like a much smaller supercar, and with front-wheel drive and a less-powerful motor. Some of you have to admit. If it were larger and wider, it would look a lot like a supercar. I'd sure like to experiment with rear wings. I don't like the criticism of "ricing" out cars by tacking on a rear-wing. I look at it like a way to make a street car into a touring car or a low-level grand touring car. And to me, that's a bit of a step in the direction of the Tokyo Xtreme Racer series. In the TXR series, you could choose what aero parts you wanted to use for the car. You could turn it into your own race car. Since I guess that choosing appropriate front bumper, rear bumper, side skirt, and all that for your car or van or truck would take a lot of work for all the cars in the game, a rear-wing is still a good way to turn your ride into some sort of race car.
I'd expect to perhaps see some good matching wings for cars. For example, I don't think I'd see a "whale tail" on a Honda/Acura NSX, a double-decker rear wing on a Camaro, or an Escudo rear wing on a hatchback. They should be very fun to experiment with. So give it a try.