ehh. heres a car i was working on
didn't feel like putting it in the contest so heres what i did:
tinted windows
changed rims
changed front bumper
tried at making a carbon hood
Instead of trying to do a carbon fibre hood by just colouring it in black, follow the PJ tutorial (http://www.photoshopjunkie.com/carbon_fiber.html) and give it some texture and try not to make it so dark so it looks different from the windscreen.
I would work on the back wheel as well, other then that you're just peachy!