Very cool! This is exactly the type of game I'm interested in making. I'm normally very harsh on platformers, because, although I love them, I don't think they are very original. However, here with the metroidvania elements and the grab mechanic to slow your decent, you managed to make a platformer that feels very unique. Props on that.
Overall the style and the music are very well done. The level design was also very good to teach the different mechanics and offer an optional challenge when I wanted more. I don't think the game is too hard, but I'm an experienced platformer player, so take that with a grain of salt.
I love this, and wish to see more from you in the future!