Looks nice! I would say that if you wanted a maneuverable robot, this is definitely the type of drive set up you want. One thing you didn't specify though: how far are you lowering the center wheel? Team 1726 had an almost identical frame geometry with the center wheel dropped 1/8" and it handled beautifully; the turning was excellent and it didn't have any noticeably rocking on carpet.
The only thing that really jumps out at me is the lack of cross bracing; you may want to have more reenforcement if you plan on going to a regional like Davis again...
