I didn't finish my game for this jam but thought I would try your game out after requesting some feedback in Discord! I always find is super helpful to watch Kris play my game on the livestream, so I've done a recording for you that I hope will help: Overdrive Oasis by WLHib | Cap Recording 😄
What I really liked were the visuals and vibe of the game, you've really hit the aesthetic and feel you're going for
My key bit of feedback is getting the player into the game as soon as you can and maybe trying to show the gameplay as an alternative to telling with the instructions screen at the start. You will see in my recording that I wasn't sure I had to jump into the rings even after reading the instructions, there's a version of this where you press start, land straight into the jet ski world, and drive into a few rings, instantly rewarding for the player, and/or having some onscreen UI helpers of the keyboard inputs?
One idea from me is having low and high rings, with low rings around the player in the starting zone that are visually distinguished from higher rings that require jumping