Cool entry, very polished and amazing art style! I like the concept and I think it very well suit the theme!
After some run (like 10 or something) I got frustrated to have to restart from the beginning every time, especially when I acidentally crash into something as soon as I went deep. Checkpoint of some sort could help dumb player like me to enjoy the game more. XD
The thing I liked most are the atmosphere and that sense of unkown the game give to you, It really makes me want to explore and find new creature and curiosities that lies under the surface.