I like your ideas for their leadership, perhaps not the naming one but yes it could be passed from person to person and it could be a descendent of the original founder of them who helped Nicky. They take in 'outsiders' to keep the genetics going and not be all inbread but yeah its basically a 'Royal Family.'
I see them arranging matches/couplings/marriages in much the same fashion as Clan Freeborns. I'll have to think of a new naming convention for their Guildmaster then, any suggestions? I wonder who the first arranged match would be and why?? Hmm, story possibilities...
I like the idea of there being an 'out' for some lower castes into the Guild, either perhaps as a kind of reverse tithe (need to mix up that genetic pool) or perhaps as something very very clandestine, a kind of slave railway kind of thing that offers a very dangerous out for those who want to leave their Caste etc.
As I said, human trafficking is not above the Clans but I wonder how any Terrestrial Lower Caste would or could make the transition to the Guild? It may take a certain mindset to adapt here that many just do not possess.
I'd say they're not overseer's, rather 'observers' who might report back to the saKhan or leader of the Watch, they could even be a Watch agent themselves.
You say potato, I say patato…. I could certainly see them referred to as observers. I wonder if this is a reward assignment for Police Clusters within the Clan? These third rate Clan militia might welcome the assignment.
Perhaps such a race could even be their 'trial of position', like how someone could try for a Trial of Position to get into the Scientist Caste by doing a PHD in X time or something. It could also be used as a trial against the Clans if they so chose to do some kind of trial to make them feel better.
I don't know about that as I was thinking more of entertainment than an actual ritual competition.
Another thought I had today questioned if these long lived spaceman would even see the value in such a quick event. Even a marathon might seem speedy to them. A question of mindset I guess.
On another tangent - could the Free Guild actually date back before the Clans? It sounds like a very Union type of organization perhaps composed of skilled tradesman that were in limited supply between the First and Second Exodus. Perhaps they were originally put together during the Star League in Exile days and then transitioned to their modern Clan successor?