I'm one of those people who don't use SOC as social status. It's basically Charm like the Companion. In CT to have it be societal rank because SOC didn't have a fixed modifier. What, if any, effect it had on a social skill task depended on the situation. In MgT2e, though, the effect is that every lord is socially adroit and street scum are all pretty bad at social skills if taken literally.
I use SOC as is (it makes a useful score and modifier statistic for Social Standing related interactions), but I think a Charisma stat would have been highly beneficial alongside of it as a true UPP "Personal Stat", as they are two very different things and can both have a "Social Impact" in different ways. Someone with High Social Standing and Low Charisma/People skills, and
visa versa are both meaningful character types. (And being High on both or Low on both are interesting Character types as well).
IMTU, the family and descendants of someone with an Imperial title are nobles, but don't have any title besides Lord/Lady unless they personally do something to get one. Knighthoods and other titles are things that could be acquired during Chargen.
Another personal change I make is that jobs aren't hereditary. The Duke of Regina's children are wealthy nobles, but they don't have any claim to the job "Duke of Regina". Obviously, intrigues and corruption can affect that in some cases. But "Duke of Regina" is a civil service job that makes you and your descendants nobles, but it isn't hereditary.
The only thing is that sometimes due to the distance involved from Capital, and depending on what the position is, it may be beneficial to have the job be something one is trained up to inherit for regional stability reasons. Perhaps like the early post-Norman Conquest "
Earl" in England which was initially a non-hereditary posting for a
Great Landlord (a "
Baron") to oversee a city and its surrounding "
County" (like in France at the time). But Earls would often try to have their offspring appointed as the next Earl if at all possible.
Perhaps the "Frontiers" like the Spinward Marches (due to distance) would benefit from the original statement about them from CT that "
they have extensive provision for home rule" and the Dukes and some of the lesser nobles might benefit from easier than normal succession-appointments for their offspring as long as they haven't screwed up and their heir-apparent isn't a loser.
Dukes:
My personal thought concerning the T5 system as regards the Upper-Level "Greater" Duke (F) is that the
appointment of
Subsector Governor and the
Rank of
Greater Duke (F) must both likely be Life-Appointments that can be actively reaffirmed in the next generation by the Throne. The way the system seems to work in T5 for promotion is that all "Dukes" are normally promoted to
Greater Duke (F) by first being elevated to
Lesser Duke (f) and then receiving an additional elevation. Both ranks have separate fief/land-grants (the greater twice the size of the lesser, and they are nominally cumulative since a
Lesser Landed Duke (f) is normally appointed to an "Important" world that is
NOT a
Subsector Capital, while a
Greater Landed Duke (F) is
specifically appointed to a
Subsector Capital.
That suggests to me that the situation is something along these lines:
The Subsector Capital is static and is the place where the Imperial Administrative Bureaucracy and Imperial Naval Administration (apart from Naval Depots and Bases) are tied to and cannot casually be moved (IISS XBoat lines and IN Courrier lines go thru here, etc.).
When Nobles are first elevated to Duke, they receive the title of Lesser Duke (f), and if Landed it is associated with an "Important World" in the Subsector.
When it is necessary to appoint a new Subsector Governor, one of the Lesser Dukes (f) will typically be elevated with a new (additional) title to Greater Duke (F) that is specifically tied to the Subsector Capital. If he does well in the position, he might expect his heir to be granted the title in turn if qualified. If not, then the family will relinquish the Subsector Governorship (and the Higher Ducal Title (F)), and another Lesser Duke (f) will be appointed to the position of Subsector Governor at the Subsector Capital, the old family returning to their Lesser Ducal (f) holdings that they had held (and have continued to hold) while Subsector Governor.
The Subsector Capital does not move with the establishment of a new appointee to the world of the Lesser Ducal (f) appointee's already established holdings, rather the appointee moves to the Subsector Capital with a set of additional granted Lands and holdings as long as he holds the Subsector Governorship but does not relinquish his Lesser Ducal (f) title. The Greater Ducal Title Holdings (F) will be relinquished if he loses the appointment, however.