Interesting game. I like the idea, just a couple of critiques: the movement really doesn't feel good. Maybe try adding some acceleration at the start and deceleration when you stop and make the jump a little less floaty. Adding little tricks like coyote time and jump buffering would also make it feel a lot better. It would also be nice if the camera followed the player more exactly instead of lagging so far behind when you fall down a long way, that way you can see and avoid things that would hit you as you're falling. There's loads of potential here, and with just a handful of changes, it could be a really great game.