Textures are of course placeholder atm, marble will be changed (actually slightly different now) and currently the bouncy platforms are red so anyone giving me a map knows how to show a bouncy floor without having to explain or have it look weird.
When you say movement sensitivity is high, you mean that the marble moves a bit fast and has a fair bit of inertia for stopping?
A bit more on physics design:
The general game design is that you need to really take into account the marble physics to do the maneuvers you need. The game is supposed to be fairly difficult, and therefore the levels are short, and it is incredibly easy/quick to restart.
As a comparison, in a game like Super Meat Boy, the controls are tight and you can change directions in an instant, however, the levels are brutal and in some cases pixel perfect accuracy is needed.
Here, I want the same sense of speed and fluidity of motion, where you never really stand still, but the levels are nice and curvy, almost nothing will kill you, and you're only racing against yourself. The requirement is that you master the marble's physics so that you can throw your marble's inertia into doing what you want, faster than you thought it could.
When you get a whip around a corner, and bounce up onto the next platform in one fluid motion, it feels fantastic, unfortunately, those awesome experiences can't be accomplished if the marble is rolling slowly around the map so that it never falls off a ledge.
-- Caveat --: The physics isn't done (as the first post attests) but the 'fixing' will be so that it will be intuitive, and after you get used to it, nothing will mess up a perfect time that isn't within your control to fix. You will still fly off an edge if you were going too fast, just as you won't make an wall-hit if you are going too slow.
Glad you enjoyed it so far and hopefully future improvements will only enhance the experience!