This is such a huge work in a small package. I think the effect of that however is that it's very dense. A single area has many symbols and text formats that need to be kept in mind. Some small tweaks could be made to improve the readability, but overall I think it's excellent. If you had room, one tweak I might make is to just say "to B2" after the "Type" symbol. That way you don't even need to mention "To" in the key.
Everything has had so much thought put into it. It's really an impressive accomplishment. I could easily see this being published and sold. One thing that is more of a personal preference, but I think it could use different cover/main art. Everything else is so polished, it just doesn't feel like it's up to the level of the rest of it. Not that it's bad, the rest of the package is just so good.