This game feels like a place where I want to hang out.
It's kinda chill, but you still have to have your brain on to avoid getting stuck and climb ever higher.
So, I would say stimulating, but not stressful.
Art, sound, ambience, idea - all very nice.
It would be improved by some sort of notice that informs the player they are stuck and should reset, and a high score system to help suck you back in for the next run.