Well, I did find that it was very easy to jump against walls. All I had to do was bounce off them. That made it really easy, maybe consider making it so the player must bounce from wall to wall rather than on the same wall?
I'm not sure how much that would impact on your game play but it's just a suggestion.
That's the point of the game. If he took that away, he would have to re-do the levels. Anyways, I like walljumping off one wall.
I really thought this was a cool game. It was challenging. However, you could have let the player see more. On the second "dark" level, I couldn't time something right because I couldn't see far out enough.