Hi Geminimax! First of all, thanks for taking the time to play the game and give feedback. I hope I'll soon be able to reciprocate.
The game is indeed a bit rushed, I have not been very good at managing time and I spent most of it tinkering with the engine, without a clear design direction of what I wanted the game to be until very late in the process, once urgency to complete something came in. I hope I can learn a lot from this experience.
Different looking bullets for different behaviours is definitely on my QoL improvements list, 100% agree with you. The health/stamina/mana system is loosely based on Dark Souls 3, but I agree there is no introduction to those mechanics other than a very minimal how to play screen.
GUI was put together a few hours before the deadline and is very rough, just basic Godot nodes thrown out there. I didn't even have a working gameplay loop until then. I had to cut sound design because of my bad time management, but I will update it once the voting is done. I forgot to remove the UI slider, but I should, it's confusing. Sprite art is good because that's the only thing I didn't make myself, but my brother did :) I'll tell him that.
Thanks again, looking forward to play your entry soon, it looks very charming.