Yoo thanks for adding to the feedback! :D
I'm also dissappointed that I couldn't get the actual rhythm side of the game working. Having never programmed rhythm-based spawning systems, I was looking at manually timing individual spawn sequences in time with the music I'd remixed... so, all in all, I cut lots of corners to end up with less stress, but ultimately a less fun game. And yeah, the loss of heads ended up being anti-fun - losing because the game decides to get too fast is kinda lame. With more playtesting and reworking time I'd certainly have adjusted that out.
Solo devving a game jam definitely has it's ups and downs, but I'm pleased with the end result. Always good to look for what can be done better next time though!
Thanks for playing! :D