I found a glitch that enables wall climbing.
Wall climb left: go to the right side of a wall, and spam left key and up key.
Wall climb right: go to the left side of a wall, and hold right, then spam left key and up key.
Oh and I was facing an issue with the mouse sensitivity; I don't think that mouse sensitivity needs to be increased; I think the issue is of which type of computer the person playing has, so people with low end computers will have very low sensitivity, while people with high end computers will have a very high sensitivity.
If I may, I would suggest using your engine's fps in a way for the games sensitivity to be same in all computers.
But overeall, I really liked your game and hope to see it be even better in the coming future.