The polish in this project is very nice - the voice acting and music was top notch, art is high quality, and the story was integrated into the game well. Mechanically the option to use other keys would help with comfort, and having the keys moved from the side to over the main game would allow you to see more of what's happening (as you're so busy focusing on the prompts you forget to watch the story).
The ability to slightly adjust the music playback would have been a nice stretch goal, as I found it sometimes went out of sync and I occasionally had to not play along with the song but focus solely on hitting them when they crossed the input areas.
Each level took me three attempts, so the difficulty (with a little luck) was great for a game this size. All in all, one of my favourite submissions.