The other week, I finished the first very messy, very crude outline for Always Outnumbered, Never Outgunned. I've learned not to let such things bother me; the initial steps with anything new (especially something this much of a left turn for me) need to be messy and undisciplined, the better to let them come into whatever full flower they have to bloom into. Let that happen first, then prune.
Next week, and through January perhaps, I'll be rewriting the outline and making it into something that someone other than myself might be able to read. It's tempting to turn that into a pitch for the story, the better to sell alpha and beta readers on it, but that's not how this should function — it's better thought of as a roadmap with a lot of detail and color, not a sales brochure.
Working on pitches for my stories has always been tough. You live with anything up-close and personal for more than a few millysex, and you develop a distorted view. The things you think are most important about it turn out to be lousy ways to get people interested in it.
Software developers actually face this sort of thing all the time. They have some brilliant technical idea (example: consensus of work across multiple asynchronous machines), but few people except for other programmers will ever care about it unless it exists in a form they can relate to their real-world experiences (example: Bitcoin!).
People — specifically, authors — may think a concept for a story is what sucks people in (time-traveling ninja fight extradimensional demons who manipulate the power of human mythology, etc. etc.), and it typically is. But what keeps others there, and what makes them want to come back and look more deeply, is what kind of human experiences they have with it. AONO has what I think is a nifty concept — I'm going to wait until it's baked before talking in more detail about it, though — but it won't amount to much if by page 100 the reader doesn't care what happens to these people.
That's the tough part with the pitch: it has to invoke the concept, but also give people some hint of why they should care about who it happens to. With AONO, I'm hoping to do that by way of the main characters being people who have seen glimpses of better things for them, but realize they're going to have to destroy everything they have depended on until now to get it.
If it was all just about a concept, I would already be done.