[EricH]

Rule #1 of FRC drivetrains: NO swivel casters.
Rule #2 of FRC drivetrains: See Rule #1.

If you must use casters, use ball casters. They're easier to work with, as they don't quite have the tendency to force your robot in the wrong direction that swivel casters do. Omni wheels are better still--but it's kind of late to get some if you don't have them.

"Big slick wheels": I'm not sure I understand that. AndyMark 8" wheels with no added roughtop tread? A bicycle wheel without a tire? The 2009 6" KOP wheels? Help me out here.

The compressor shouldn't be a problem--ideally, your tanks are charged when you go onto the carpet.

You pretty much have two options right now that can be implemented easily:
1) Slicker wheels on the front. That's dependent on what you have available; a large box of zip ties or a roll of duct tape can make a wheel less sticky in a hurry.
2) Shorter wheelbase. There's a couple ways to do that; either move the axles closer together or use the lower hole on the chassis (if you're using the KOP chassis) to add another wheel, and power that. How short you need it to be... well, that's something I'm not sure about.

I'd go with option 1 right now; option 2 will take more time, more parts, and is more complex.