Cool concept! Don't think I've played a 2d climbing game with grappling mechanics like this before. There seemed to be a lot of work put into making the grappling mechanic and it turned out great, but some other more basic platform mechanics were a bit overlooked. Since its a platformer at the end of the day, maybe some more investment in improving the basic movement would help. Also, there seemed to be a bug affecting the player's jump, maybe the hook was colliding with things even when its not shot out?