Rolling is fun!
I liked the core mechanic of the game, but felt like level execution could have used more iterations. The difference between the second and third levels was jarring to me. The bats are annoying as enemies because they can kill you in one touch, and since your movement is so dependent on inertia, many times I would bump into them by accident, with no real opportunity to steer away or do anything to prevent it. Also, for some reason the music and sounds were too quiet, although maybe this was just my problem.
Anyway, thank you for the game! You did a good job, hope some criticism will not discourage you.