(Dilettante has a lot to say about this sort of thing, btw.)
It all depends on the character of your interpretation of the universe.
Given the way that Imperial nobility works, lower ranking nobles could be more like what we would call "Trust fund babies" these days. You could easily have a character who was just cut off from his trust fund, and still tries to throw his weight around, often successfully, even though he may not have the resources to back up his threats.
Or the character might command some level of respect on worlds near his home world, and in general his overall demeanor would still grant him social interaction bonuses (of the "You seem like a fine, upstanding fellow" variety).
Or the character could be a variation on the "Gentleman Highwayman" - a roguish fellow with a decidedly upper-class charm. There are plenty of "age of piracy" romances (not the bodice-ripper type of romance, the "pretend pirates weren't all flea ridden sociopaths" type of romance) featuring nobles who have either lost their holdings through treachery, foolishness or politics, and who are thrust into a life of high adventure.
For a whole different kind of high social standing, reference Inara Serra from "Firefly".
If you can arrange to have most of the players have high-ish Soc scores, you could also do "Star Wars" type situations, where the characters are the Leaders of Men (like a Princess, the dispossessed son of a Sector Lord, and old General who fought on the losing side of a recent war and a pair of no-better-than-they-ought-to-be pirates, all banded together to do <X> with the material support of a shadowy organization whose goal is to undermine the legitimate government of the sector).
