Great Job! My First CADed Chassis didn't look this nice. (i have now made 7 chassis). Make a couple more chassis and you will then definitely have a feel for the CAD you are using. This will also give you a chance to choose a basic chassis design when designing this season. Try making a sheet Metal one, mucanum/omni, West Coast Drive, Swerve (maybe). Experiment a little with wheels and gear boxes.
I have to say that I do not like how the bearing block's are set up though. Because they are sitting on the top of the lower Brace all your wight from your robot will be on two bolts. If you had them on top then the weight would be on the brace. Another option is to make plates to put on either side of the wheel. Bolt the plates to the top and bottom braces and the axles bolted to the plates.
Good Luck!!
Edit: Here is a pic of what i was talking about before.
http://s1220.photobucket.com/albums/...WheelMount.png