There is so much potential for very satisfying player controls here!
I would recommend tinkering with the grappling mechanic more! Most importantly making it reach farther, but you could also try allowing multiple grapples before touching the ground again. I noticed when grappling the floor in front of the player you can build up massive momentum, that could be used for some cool level designs!
Also I wish the jump inputs would be more forgiving, it happened quite often that I pressed a little bit too late so the frog made just the small hop instead of big jump.
Btw I assume this is not intentional but you can slowly climb walls be repeatedly walljumping, you move like 1/10 th of a pixel upwards every time.