Thanks! The bike physics are pretty slippy due in part to wanting a "kinetic hoverbike" kind of feel, and in part to my terrible physics code. I based the physics on an old gdmag article from before vectors were invented. I agree that more feedback would be great and I wanted to do a lot of those things, I just didn't have time, even pushing a few weeks out past the CGAJAM deadline. It's certainly not a super-polished game. The code is all out there, so if you want to add some features or tweak stuff, feel free, I'm happy to accept pull requests.