This was cool! I think in terms of intuitiveness, the area which was weakest was "goals". I could understand what I needed to do moment to moment to control the character, but there wasn't a clear sense of where I was trying to get to, which is a key thing in 3D level design.
I rated this lowest for "interesting/compelling challenge/puzzles" but high for "would I buy a longer version". I did this because I think the overall creative direction and mood of what you made showed a lot of promise, I think a game with this approach to art style, audio, and general mood could do very well. I just don't think the actual platforming was interesting enough... and after a long fall and failing to land in the right place to collect whatever the red thing was, I was pretty much ready to quit.
The problem with making a game which appears to be really chill and relaxed, is that if the challenge design is then actually quite punishing and harsh, the chill stuff will feel like it's mocking the player.