That was a thrilling ride, but finally made it to the end. The Game Over part somehow came pretty surprising^^
Is has maybe a simplistic looking style but it's probably the best graphics of all, your own imagination. And the whole mood fits perfect to the theme.
Really liked the story and the voice-actor was awesome. All in all a great job!
P.S.: You should think about an hardcore-mode: Each time you hit a wall you get damage. That would be insane :-D