Ok so it got me playing for I think half an hour or maybe an hour, I was completerly absorbed. Awesome work!
I would add a map, don't consider them as suggestions but a personal preference. I felt lost some times in the mountains and especially when I returned to the first area but from another point.
Also, in the part where you fall down a lot and have to go back up, I was interested in trying all the paths I saw ans many times they just brought me back down. I think it's a problem with the fact that your game initially proposes a wide range of exploration, but in that section it's mainly straight platforming, so it's a little confusing, but a map would have made it more clear.
All things considered, PLEASE make this into a full game, I love it!