This is a solid puzzle game with a good difficulty curve, and the music does go hard!
I think the one thing that would have helped me is maybe having all the pieces you can use spawn from the start and shown visually. At the beginning of each puzzle I clicked on every piece to spawn them all. I like that they stacked and I didn't have to click to spawn every time I wanted one, but seeing them side by side would be good.
Awesome job!