Thank you for taking the time to play through it! I actually put in buttons to mute the SFX and music, as I got a similar comment on another jam entry a while back. They are the speaker and music icons on the main menu, but it seems I should have drawn more attention to them! Also having a pause menu in game where those are available would be good, and optimally more options than just on and off.
I was torn on how to handle the spikes, and ended up going with them as an instakill in the same way the pits in a Mario game are. Your suggestion of having them do damage and reset the player to the start of the room is something I did not consider, and a solution I really like. I have plans for turning this into a full game, and I would definitely make them work like that.
As for the enemies, it's an unfortunate quirk of the very rudimentary way I implemented the enemies. With more time, I know exactly what I need to do to fix it, and I'd add more dynamic options and nuance to the enemies as a whole, especially the bosses. There was a lot I wanted to add, and I was okay with kind of dumb enemies so I could dedicate the energy elsewhere, but in a full version their behavior wouldn't hold up. I think that would address the crouch partially as well, more enemy behaviors that challenge different mechanics. And also more dynamic map elements that don't allow you to just sit still hahaha. The big lesson I got from this jam was that enemies take a lot of work to get right, and it's ambitious to put them in a jam game.
I'm very glad you enjoyed the game and liked the designs of everything! I'm happy with how things turned out given the time and my limited skill with sprite and animations. There's a lot I can improve on, but this felt like a breakthrough point for me in that regard! When I end up expanding on this, I plan to add more of the stuff that worked! More enemies, more pickups, and other things that interact with those and enhance the experience. I appreciate the critiques, they are very insightful and I plan to consider all of them when making a follow up to this game, as well as other future projects. You'll definitely be seeing more from me!