This is really cool, cute and clever~
I just conceptually love tying a journey of self discovery to the progression of visuals and the music. It's a really great idea.
I think the main critique I have is with the scenario. That being that there isn't really any conflict (internal or external). Or perhaps a better way to put is that there isn't any "resistance." I think for a journey of self discovery, for it to really hit home by the end, there should be some sort of struggle that was overcome. But the way it plays out is that Ruukoto interacts with something or talks to a character, takes in information in a neutral or positive way, and grows/learns. And there aren't any significant, narrative roadblocks to this procedure. Which, for me, left the ending feeling a bit hollower than it should've been. I think the music and dialogue in the ending itself were great and really sold the moment in a vacuum, but there was just kind of a feeling in the back of my mind that I didn't really "earn it."
To put this in less abstract terms, and tie it more to the theme of the story as I perceived it: It's one thing to answer the question "How does one learn to appreciate the world and their existence in it?" But I think a more interesting version of that question would be "How does one learn to appreciate the world and their existence in it, in spite of the hardships one might experience or the wrongs one might witness?" And I think adding and answering that additional context to that question is what would've really pushed the narrative over the edge for me.
Kind of a ramble-ramble, but hopefully that makes sense lol
Lastly I wanted to give particular mention to the music. I adore "Exploration Layer 3" and "The Joy of Life" in particular, props to the composer~