Tips for the Post-jam version:
The dancing scene is cool, but I spent all my time looking at the arrows, so I didn't get to look at the dancers. Maybe move the arrows to above the player avatar, or overlaid on top?
Give the arrows some different colors and give them each their own "slot". My brain couldn't process them fast enough without additional cues. It was just a bunch of white circles coming down fast. Too fast for me.
Make a much easier intro or tutorial level.
I'm not sure how you did the beatmatching. Are the arrows cued to the music? I couldn't tell.