1. Do NOT do any drop shadows..... They will not be easily transferred to different media.
2. The colors are OK.... They aren't crisp. They aren't eye-catching. The tannish in the middle kinda screams dirty to me.
3. The car in the middle does lack any sort of recognition. Placing a car head on is tough. Stick to a side-view with a vehicle.
Good luck... Hope my comments help.
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