I haven't got past the spectral hands section. In that one, it seemed like the hands move way too fast, you can avoid them for a few minutes and then you suddenly get caught out of nowhere. Not to mention that with the mazelike corridors, it's very difficult to figure out where you are supposed to go.
And if you get caught, you have to start the game (or atleast that chapter) all over again, so it's very frustrating as well. If checkpoints can't be implemented, maybe some HP mechanic would be a good idea.
The only thing that's really needed to be added when it comes to the visuals are some kind of movement animations for the protagonist, it feels weird seeing that sprite slide all around the place. Otherwise, the game looks good and the theme seemed to be implemented in a very nice way with that piano!