Visually, the game is amazing. Everything comes together super nicely, I think that audio would've really helped.
I think the pacing is a little off. The game is challenging(not too challenging though.) The concept is interesting enough, but the amount of time you have to wait between getting to try again feels too long.
I think that the first time you descend, the length is great. It should be slow, and build suspense. It is only when you are trying to go back down when you already know what's going to come that it feels annoying.
Still, it was a nice game! I actually made something kind of similar for a game jam last summer.