First of all, thank you so much for your comment and feedback, we really appreciate it!
I will add a volume slider once I can update the game :) and we will try to upload and release the soundtrack on SoundCloud this week.
Regarding the gameplay, I agree and I really like the idea of the music affecting the gameplay. I am very much a super beginner at coding, this only the second game we make. Last game jam it took me a few hours to just make a start page with two buttons, just to give some context haha. For this one I had planned on having much more art and get the room to flourish as you get further in the game.
Thank you again for your feedback and for seeing the potential, it is really motivating :)