Wow I actually really love this game. There is a good variety of mechanics and powerups, and the bosses are great in how they make you predict their movements and use powerups you've gotten before.
I especially love the visuals and music!! They give this game such a unique and charming personality that I can't say many other games have. The story + cutscenes are also cool, and they help frame the gameplay well and remind me of the Binding of Isaac.
There are two easy bugs you could fix though. One is that you get stuck on the sides of walls. Make sure the physics material on the colliders don't have any friction. And another is that the projectiles you shoot are treated as the same tag/layer as the player, so e.g. if you shoot at lava, you die.