I definitely need a Twinkle Twinkle Little Star puzzle to match my level of musical prowess.
This is a very creative and very challenging game.
As a suggestion to adjust difficulty, maybe give the option to limit the actions. Like no pitch reversals, or no order reversals. A segment sequence only could be an easier way to get started before progressing to more dimensions and challenges.
I hope you continue to develop this. It's a solid concept.