This is such a gorgeous SRD. It's a work of art in its own right. While every other SRD I've read treats the process of breaking down the mechanics as perfunctory, this SRD relishes in its own aesthetics. Truly marvelous.
I do have a couple thoughts/suggestions that would be quality of life improvements:
1. I'd move character advancement up to be alongside Lessons or I'd move Lessons all the way down to be with the character advancement section. Having those two split up across the actual entirety of the document is a truly sad thing.
2. It isn't clear what Scatter is and how that relates HP and MP. Are they interchangeable? Could I replace Scatter with HP or vice versa? Most 90% of the SRD you talk about magic having a Scatter cost and then on one page you talk about HP and it makes the reader scratch their head and say, "Wait, what?"
3. Assist Pools being so far away from the section on Spell Pieces makes it difficult to understand what you use them for aside from narrating spell effects. You get a better sense of what Spell Pieces do and how spells function mechanically (not just narratively) once it's brought up in facing Encounters.
That said, these are just my opinions as I went through the SRD with a fine-tooth comb and made notes for my own contribution to the Harmony Jam.
Even if you don't think you'll use it to make something, you should pick up a this SRD, read it, and imagine the possibilities. It's a great SRD, easily the best looking SRD I've ever seen.
Thank you for sharing this with us.