We're already a guild of people who like roleplaying, no need to fracture it into smaller communities.
That being said, if it's something you want to do, just make an IC recruitment thread and go for it. See if there's anyone out there into it. It sounds mostly like you want inter-roleplay adventures and politics like multiple threads with interlinking storylines. That in and of itself is a good thing. The forum version of a West March D&D campaign xD
It's more a logistics issue of how to do it in a way that encourages beneficial things in the guild, like people getting together with new groups of people and building epic plotlines, rather then it becoming a bit of a petty mess with OOC squabbling and drama.
As
@Scarescrow said, Expanding Horizon is a very similar concept, with threads and groups of people and different planets and all sorts of things like that. But it hasn't seemed to have taken off. I think perhaps implementing something on that sort of scale in a way that is accessable to everyone is the real challenge. We don't have many options to put up supports and foundation and scaffolding to keep something large scale trucking, imo. So if you did want something sprawling and vibrant, it'd have to be a grass roots type deal with alot of people putting in the time and effort to keep it going. And
that comes with it's own issues.
I think perhaps if you wanted to do a thing like that, you'd need to either simplify it, and heavily keep the focus on the roleplay aspects and what you want to achieve with it. To be honest, there are alot of roleplays out there that have IC factions and they work just fine. It's the pulling that into OOC in a way that works and doesn't devolve into a hot mess, I don't think this forum is really the type of place for that.
My favourite thing about this forum is that it's all pretty chill. You have only four types of categories where all the roleplays go rather then a website that splits up the 6 fantasy roleplays from the 2 sci fi and the 30 slice of life ones, making everything move a little slower. I don't know, bringing OOC guilds into the occasion doesn't seem to mesh well with the structure in place here.
Maybe as a small time event deal for a while. You could have kawaii desu desu badges you give to newbies along with balloons and cookies and stuffed animals. Could be fun as a smol thing. Or have some Spam games about guild allegiances.
Anyway, thats my stream of consciousness conflicted barf for the day.