Yeah these are all just small previews of content for a much larger game, the six main biomes I have fleshed out. My intention is that it will ramp up through the game, getting to the crazy hard platforming like that laser room that requires abusing time travel to brute force it- but ~then~ I can start introducing the more complicated gameplay elements: Enemies and traps that manipulate time too. Some more direct like 'drain or disable your rewind', or others that can drag you back in time, or travel forwards in time regardless of your rewind, or fire projectiles that travel back in time and kill you in the past...
Crouch slide is getting a lot of attention from me to tweak it, definitely the most maligned. My last update made it respond only to how long you hold it, but I think it might still need a different input like you said. I am not sure about ledge grabbing, I made it ignore ledges if you hold the down button now, but I wonder about making it require you to hold left/right