Thanks for the kind words and thank you for playing!
You are definitely right regarding the movement and the annoying run backs. I wanted the jump to be slow, to force the player to be very deliberate with their jumps and build some tension. But after dying far into the game, I also get the urge to just speedrun.
I also made a mistake with the level design, and had a few too many horizontal sections. If the game was more vertical, the player could learn where it would be safe to fall (as well as create safe platforms using the corpse mechanic), and then very quickly get back to where they were when they died last.
Oh well, lessons learned!