As someone not really experienced with rythm games, I didn't find anything wrong with the gameplay. I thought it was pretty good overall! My main criticism would be that it's hard to read the story and understand it properly because it all appears on loading screens so it's easy to miss or even know if you're reading it in the right order. Also it would be nice if there was some point to selling/making potions but I get there wasn't time to implement that.
The animation for the potion coming out of the cauldron tho, idk what it is but I love it so much.