I really can't complain too much except for adding a couple features, at the title screen it'd be nice if you could type instead of clicking to choose a mode. Another small feature would be to have a failure screen that shows what you missed, and the romanji for it in case you forgot, that way you don't have to go through the chart to remind yourself. If you could add these 2 things I would play this non-stop til I have mastered all difficulties.