I think the important thing to remember about Solution Nine is exactly where the zone sits in terms of 'content type': It's the secondary city. It's definitely connected to Heritage Found, and we'll probably first visit them very early; perhaps in that 'pick between two mini-branches' part of the questline, same as we did with Eulmore and Radz-at-Han. I think more Radz than Eulmore, because I believe before ShB's release they were already making it pretty subtextually clear that Eulmore's Up To Some Stuff in a way they're just not with Solution Nine. This also means that, while it's probably going to face a change of some kind to explain why we don't have full access to its services at first, it is going to... y'know, still be there afterwards, and is highly unlikely to overshadow the rest of what we've seen, which is of a very different vibe.

I'm guessing that we'll be seeing an overall conflict of 'traditionalism versus modernity' in Dawntrail--likely not a literal conflict, since it's been made very clear that Tural's all cool with each other, more just everyone having to grapple with that question in their own way. And to aid that whole thing, Solution Nine's situation will be largely 'self-made'; not elevated by some externality like shard travel, but developing entirely by its own propulsion and will.

Basically: I think it's FFXIV Wakanda.