I liked graphics and audio (music would change a little smoother). Controls are hard but overall it is fun to play when you get what is going on :)
It could be a nice speedrunning game but I see a few things that would be fixed:
-restart does not restart the level but players position. Imho it would be better to reset everything in this case.
-Font is too small, I couldn't read anything. It may be a bug.
-Mouse control of the grappling hook - it would help a lot.
For 48h it is a good game. Worth investing effort to add new features and improvements so it could be released commercially :)