There are about a million zillion things I'd like to write re: the TE setting, and a more extensive exploration of the aristocracy is just one of 'em. At this point, though, we're going to have to wait to see if sales of the setting justify doing more books beyond what we've already got scheduled.
In the meantime:
1. While I don't have time to write any DH articles about TE, there's no reason someone else can't. They'll get the "not canonical" label, but that's not to say they might not prove highly influential. 
2. I'd say you can pretty much make up whatever sort of aristrocratic titles you like. Given the plethora of families, planets, and species, all sorts of bizarre combinations are possible. The whole arrangement could make the Germanic title system (something I recently researched for FH) look positively well-organized.
Steve Long
Young Curmudgeon
Bookmarks