[echin]

Some thoughts:

I'll echo the above comment about actuating the center wheel to get more down force. My FTC team is currently using an H-drive and having a center wheel with variable down force has proven to be very important for smooth driving.

Also, it might be a good idea to reinforce the drop down wheel modules a little more. They look like they might bend easily from a side hit with the traction wheels down.

Overall, this looks really good. I'm curious to see how it develops!