Nice idea!

I really like the concept of this, where there are various related hand gestures that related to different movement patterns, it creates a very unique theme and aesthetic for the game. I can image other hands that could be translated into movement, like a Halt for stopping the players movements.

Although, I think that this game could benefit from some finer tuning of the controls. There are a lot of things that can be learned for making fluid and good feeling movement for 2d platformers, and most of them aren't that intuitive unless you already know they exist. There are obvious ones, like there being a strange delay for the jump, but other things like coyote time (letting the player jump for a few frames after they've left the ground) and input buffering to allow early inputs still be allowed can go a long way for fluid movement.

I also think that the flick hands should be consistent in the direction they throw you, rather than the direction the player is facing. Since it would be hard sometimes to consistently use them, but when they do work they are very fun to chain together. You could also repurpose another hand object into having the players facing direction considered for its launch angle.

With mechanics like these though, I think this game could benefit for a more level based style, where the player goes through a series of challenges to beat a course. Similar to how Celeste works. Then you could rank up the difficulty without the player getting frustrated by having to get all the way back if they fall down.

The pixel art is very clean, but it could still use a bit of touching up. I think namely the player could be re-sprited a bit since it is close to looking like its on a different pixel ratio than the rest of the game. The ground texture is also on a higher ratio than the rest. But this is all nitpicking.

Good work! It would be great to see some post jam versions of this!