Good concept. I liked the dual grappling hooks. I kind of not liked their controls, though; even though it is a part of the game. The fact that you need to hold LMB/RMB to keep the grapples on while contracting them was a bit tiresome. Having them stay after releasing the buttons would've been less carpal-tunnel inducing, while keeping the game's core mechanic unchanged.
Still, enjoyable! Cheers!