The grappling and inertia are really cool to have, reminded me a lot of Tribes (I would appreciate having the jet ski from there that completely removes the friction between your character and any surface it is sliding through). Would be cool to explore that mechanic more than in a couple of segments (the lava corridor was quite a challenging puzzle, maybe having a checkpoint there and some simpler section just before it to get used to the movement would make it less frustrating).
I accidentally killed the boss with one shot as soon as the leaves started, not sure if there is something else after that (couldn't find any way forward from that arena).