My character kept getting locked in position, especially when I reached the bendy-ball guy after the ice level.
You might also want to do something about the ball getting locked into a narrow vertical path. It's not much fun when it takes over a minute for the ball to cross the screen, and if you should be unlucky enough to get it on an even narrower angle, it will bounce up and down at increasing speed until the ball disappears, meaning you have to restart because there's not a fail condition.