maybe a game mode where you have two overlays, one to activate platforms and one without. this isn’t the theme (this’s been used before), but it serves as an interesting twist to the platforming.
maybe try a slope jump dropper where when you enter the level, there’s a timer. once it reaches a certain time, the exit to the game appears, but the issue is that the zones are closing in. the starting area will be unavailable and the floor isn’t able to be walked on, so they have to continually hang onto the slope jump until the door appears. i explain things badly, sorry bout that
drop jumps, but the middle part slowly gets more tilted and the drop jumps harder, until the drop jump is impossible and the tilted middle is a slope jump, which is easily able to be jumped over. basically a succession of drop jumps ending with a secret slope jump