I wanted to add that regarding difficulty, I feel this is a matter of taste and direction. I don't believe in too easy or too difficult, just know your target audience, and know what you want to convey with your game. This game starts off really easy, but quickly ramps up, but given the nature of the game I feel the difficulty is fine the way it is. Each attack is pretty easy to avoid once you know it (unlike undertale, is damn hard even when you do know the attacks), so it's just a matter of being persistent (which is fitting for the theme of the game).