Regarding the round theme, I’ll have to admit I didn’t get much of a story vibe - there was certainly some character to the different levels though, I got to someway through the third where the orange orbs were introduced.
Edit: I read the description again and see it’s about getting over depression. I’m guessing there’s some macro theme relating to how the levels evolve or maybe other tidbits that come later I didn’t see. Unfortunately, can only rate based on what I saw - so if anything, might recommend front-loading story beats through environment.
But looking aside from the storytelling category: Checkpoint system was nice indeed,I had to leverage it a lot. only concerning thing was that momentum pre death was carried after (so if I was dashing, then died, I might still be accelerating on rebirth and just die a lot). Probably starting from a neutral speed would be better. Also mechanically, the green orb I think should either be auto-use right away on touch (and therefore, it makes the the blue barriers more like narrow corridors), or make it so that you never have them so close to the barrier that you have such a tight turnaround to press. I dropped off on the section where I had to go through the blue, reverse direction, and get greens right before and after. The fact that I couldn’t slow down or control my speed of reversal started to feel more frustrating than anything after a bit with the spacing in that specific example.
All in, nice gameplay functionality!