First thing that really struck me as nice was the sound design. There's something extremely pleasing about the little start up sound and all the other incidental noises.
The game-feel using the keyboard was BEAUTIFUL... and I realized this was meant for tilt-based mobile platforms... but as a pc game... it just feels great.
It seems you have a great foundation for a game, but I think if the gameplay was left as-is, it might grow very tedious and boring after a few dozen levels or more. Something as simple as different backgrounds, ball / cube textures, and music could really break up the stylistic monotony.
Also, from a gameplay perspective... because of the kind of gamer I am, I would imagine this to be a lot more engaging if there were puzzles within the maze to solve... like triggers that need to be pressed to open gates... maybe even occasionally with a timer. Also hazards like electricity, or water... things that would really push forward the importance of good balance while playing. Or heck... even a monster that chases after the ball on some levels that keeps you having to move and thinking quickly.
Another idea... just spit balling here (har har)... but what if instead of a Ball... it was a mouse? I think that's the kind of stylistics / out-of-the-box thinking that might make this game more memorable. I mean, the whole ball-rolling-around-thing has been done endlessly, and while this variation is nice, it might be nice to see it taken even further, or in a different direction as far as the whole ball vs. maze.
Just some ideas. Definitely a great start!