Overall I feel this as a good puzzle game. I loved the echo in the cave. Good sound design.
My initial thought was this camera is super sensitive. I got used to it, but I feel it would be a better user experience if the player didn't have to get used to it. I personally don't know what it takes to change/edit how a camera works and feels in game, but having that might make for a better time.
There were some slightly floating assets, an invisible collider when going up the spiral stairs (I think the one with the hand block). easy fixes.
good visually cohesive game. I'm curious as to how it would look if you pushed the environmental color a bit more (relative to which crystals are nearby, sorta like you have in the concepts)
I'll have you know I felt invested when platforming at the more elevated heights, so good job engaging the player.
My critique is nit picky, I enjoyed the game.