How about adding some proximity sensors to keep it from colliding with the wall? You can add a special gesture such as two taps on the control pad to temporarily turn it off when you intend to collide with something.
I'm still working on the steering settings (expos and rates) but its not too bad, well better than my last 2 wheeled bot anyways. I was also trying to drive all fast and I think I should really lower the max throttle so it's no so squirrely