Nice first full project, Nate. Here are a couple things you can check out to help you iterate; another person a while back had a similar idea.
http://www.chiefdelphi.com/forums/sh...ad.php?t=95179
http://www.chiefdelphi.com/media/photos/36921
As with the above project, it could be a great project to make in the offseason to test different drives, but it most likely is not the practical design for a competition robot.
Also, this may be a good chance for you to learn how to create configurations of your assembly within Solidworks.