Rework/Clean up rendering and prep for printing

Looking to work some magic quickly on this pic and prep it to print at 12”x18” size. I think adding some drama to the background and adding "Do More"(in Avenir Medium font) under the Logo would do it.

The rear and front wheel covers also need some clean up. The rear has a few glitches and the front has the flow lines overlapping the body parts a bit.

Let me know if you can quickly help. I'd love to get this off to the printer ASAP ;)

Thanks!