I agree, the game would benefit of some music. Sadly the time didn’t allow me to compose a song, neither search for one.
I don’t know why you think the limitation isn’t being used. The Ent wants to lift the curse. The Ent is cursed and it’s spreading it. The intro explains that.
The game doesn’t have weird hitboxes, just lack of particles indicating the range of the curse, which is a bit bigger than the Ent’s collision box. Although I agree of the hitbox of the “Heliflower” (the shuriken/windmill flower) is janky, because it can collide with the Ent.