Interesting interpretation on the theme, we actually had a similar theme in the past (Metroidn't), to which this game would have fitted perfectly. Unfortunately I feel like the process of giving up powers was not rewarding in itself, as they were basically just keys. When getting an upgrade in a traditional metroidvania, it works because the ability actively interacts with the environment, which is not the case here (though admittedly, it was a challenge for what you were going for). Others have talked about the assets mixmatch, to which I agree, and I'm hoping the fairy has an actual purpose, maybe lore-wise, that hasn't been developed yet. If you do plan to keep working on it though, I think you have a nice foundation. Keep it up!