I have a lot of thoughts that I'll try to organize constructively.

The scope is immense. The top priority should be writing an elevator pitch summary of the vision. Each of the 5 areas listed are being worked on my many in each field and what's lacking is how these come together that makes it cohesive. Being unable to express it could be a sign that it's not as clear-cut 'a thing' as envisioned.

Being able to distill all these ideas into a summary has been elusive. It could be approached like a startup, produce an MVP and iterate keeping what works and refining others that don't convey it well. Like an MVP be ruthless in cutting scope to only the bare minimum that form a kernel of the new concept/idea, rather than piling on supporting ideas that only dilute into murkiness.

Now here's some cautionary notes. I'm picking up the distinct characterization of a perfect project that has yet to be executed. Very much like a project in the garage that's perfect 'in mind' before any physical form is produced. To think that it's been 10+ years with 2+ years of refinement, and yet there's no actual text. Hand-wavy descriptions which are too terse to refute maintains the perfection of a vision. It's sort of like string theory but without the math.

There was a point that writing "Book One" hopefully wouldn't take 10 years. I think that should be re-estimated based on past velocity. If any person could write a compelling cohesive book covering this scope in a lifetime, that would be a great achievement. This situation is not unlike perhaps many would-be authors working to publish their first book. The stakes seem raised to the highest levels though. Normally the consequence is that a work of fiction didn't get published or it did but wasn't well received. Here is the belief that there was a great vision that didn't get communicated.

Normally I would dismiss anything that isn't clearly communicated as feelings and ruminations. That might be insensitive or not well received given the time spent. I would suggest actively and objectively working to make sure that you're not in a 'thought bubble'. What might be some ways of doing these 'self checks'?

There was mention of removing ego in this work. Be more strict on this. Don't use 'I/my/mine', whenever writing or even thinking about it. Also think of it as 'a vision' giving yourself leeway to adapt it.

Other notes I didn't know where to say them:

> staying true to my vision, while making sure to be open-minded to feedback

Presuming the former means not actually doing the latter as it is entertained but not impactful. If the vision was greater than yourself then it could/should be a shared vision that is the product of many incorporating any/all ideas and contributors.

> feeling isolated/alone because no one else really understands what I'm trying to do

This has a 'No true Scotsman' ring to it in that the 'what' having not being defined can always be mutated into something that's not falsifiable.

Also check that you're not self-isolating by being too possessive with ownership. A thought experiment is if you could produce the book where no one could know that you created it, how great would that be for the world and you? If you don't get great satisfaction in that thought, perhaps it's more personal and not about the vision.

I wish I had more/better self-checks to offer. I hope you make good use of your time in a way you don't later regret. That's all any of us can hope for.