I'm no good at rhythm games but i had fun learning the systems and i had it down by like level 3. Presentation is fantastic and slick, there is no confusing the different elements of the level and its just plain satisfying to look at.
Learning curve is a little steep for rookie players, as others mentioned. I see you mentioned you were thinking about a difficulty slider, i think that would be a fantastic addition if you choose to continue or rework this project.
My lack of skill in the genre will not effect your rating negatively lol. Great work.