Thanks again for sharing Orboboros with me! The scope of the doc is really impressive and it's clear that a lot of time and effort has been put into it.
For starters, I really like the conversational tone of the introduction. Your personal journey with gaming is a really nice touch in explaining what drove you to create this and defining who your target audience is. I also enjoy the world building in establishing the world. It has a nice light-hearted tone that definitely gives the Hyrule vibe you're looking for, especially the last sentence on page 3: "To return joy to a wondrous land" is super evocative and does a great job of selling the types of stories people can tell with this supplement.
Including the three elements that the supplement is designed to support, Seeking Treasure, Exploring the World, and Facing Calamity, is another great way to communicate to GMs and players what types of stories will be supported.
I really appreciated how detailed you were in how you restated the basic system rules. It clarified a few things that I didn't totally understand from them myself.
The list of species is evocative and I really like how you included information on culture like food and music for the Rablin, Goblin, and Mothmof species. That's a very nice touch.