The whale fight was my favorite and my game crashed during the mushroom fight (I got hit by one of its projectiles, but I'm not sure that was the cause, game just froze).
Since we play using the keyboard, I'd like to pick the fight from the main menu using the keyboard too.
Just a suggestion: maybe we could have a specific ranged weapon for a specific boss-fight. Just for a change, you know? A giant bird or dragon, maybe.
Keep it up.