When I wrote about the introduction of the Patriarch, I mentioned that he never spoke for himself, but had a red imp familiar who sat on his shoulder and spoke for him. This was an attempt at world building that never came to fruition, and it's a pretty common problem for GMs.
This is a perfectly reasonable arrangement.
There's a principle for dramatic narratives known as "Chekhov's Gun," which says that you generally remove any narrative or contextual elements that aren't necessary to the story. If you point out a gun on the wall in act 1, then it ought to be fired by act 3, otherwise it never should have been pointed out at all. You could reasonably extend that idea to RPGs, cutting out the unnecessary fluff and narrative clutter, but it's not the same process as with a novel or play.
I've written at least a bit on Sar Diga before. It's a well-connected hub of commerce: It's not terribly far from the capital, it's a hub of fishing off of Lake Kheldram, and it's sitting on the coast. Merchant and passenger ships coming from the east make their first stop here, so there's a lot of commerce that passes through the city. The gothic aesthetic of the city distinguishes it from the others. It's the perfect place for a crime syndicate to make its headquarters.
Like Thief but replacing technology with magic.
The Family isn't really familial, but the ranks in the group are organized by lineage. The head of the group is the Patriarch, an elusive figure whose true identity is known only to his inner circle, the Brothers. There are five Brothers in the organization, each in charge of respective fields of crime: Prostitution (Thalia Cyanal), gambling (Haneth Tsalaxa), black market goods (Imre Levalle), and organized theft and protection schemes (Kahveh Harandi). The fifth Brother, Dimos Seeren, acts as liaison between The Family and the Boland Brotherhood. After that, the organizational breakdown goes through nephews, then cousins, then various levels of "friends of The Family."