This looks like a good start. I like the lighting and the music.
A few quick things you could do to make this a more complete experience are to
- enable players to pick up coins and add coin pickup sound
- track the players current stat such as coins collected and/or monsters defeated that can feed into a number go up mechanic
- If the beat counter doesn't tie into the current game play at all hide it because if you can't see it you won't wonder how to get it to work
I think if you want to keep the combo you may want to think about adding a tutorial to explain how to activate the combo.