I really do like this game like your other games, but I feel it takes away from a bullet hell game when your hitbox gets bigger and bigger as time goes on.
If I may say something, a lot of the attacks feel somewhat monotonous. It seems to me that firezilla's attacks are basically, hit, spinning hit, hit with fireball, hit with larger fireball, and hit with rather potent fireball. Tbh, I'd like for the 1-gauge-thingy attacks to still have a strategic place while fighting, not get completely overshadowed by flashier, game-breakingly powerful attacks.