Cool idea, but I think the main thing holding this back is how punishing it is. Starting from the beginning can get tedious very quickly, especially when some of the deaths feel unfair. In some rooms I fell into lava as soon as I entered because I didn't have enough time to react, and dying when the boomerang hits lava just feels unintuitive. If you fix those things, there's the potential for a fun puzzle platformer.
Also, I'm pretty sure it wasn't intentional, but I actually love how the character twitches uncontrollably when they jump!