Some of those ideas aren't too far from what I was thinking, actually. Rather than have a big sprawling New Rebupic, or Galactic Alliance or whatever, I was thinking the galaxy would more likely have splintered into a number of smaller empires/kingdoms/republics/corporations/theocracies/etc. I also have little interest in the Yuuzhan Vong (sic? Who cares?) but from what I understand from Wookiepedia, it looks like I don't have to mess with established Star Warsiana to remove them, since they went extremely underground if not essentially disappeared following the New Jedi Order series of books.
So, I'm thinking there will be a New Republic or Galactic Alliance. The heir to Leia's efforts to establish a new government post-Endor and all that. There will have to be some entity that's a descendent of the Imperial Remnant as well. I think a New Mandalorian Empire would be interesting as well, as well as a number of multi-system corporations, alliances and federations of all kinds.
I think Luke's Jedi Order would not necessarily resemble the Old Republic's version of the Jedi Order; Luke was successful in many ways because he didn't follow their doctrine. He didn't avoid attachment and focus on dispassion; he got married, hung out with his sister and her family, and let compassion be his guide. Without it, he would never have been able to effect the redemption of his father either. So, I imagine the Jedi Order is a bit more activist, and probably a bit more divided, as multiple opinions about what it's purpose are are voiced. In fact, I can imagine more than one order that either utilizes Jedi like teachings, or even claims to be the "true" Jedi. Probably the one most closely aligned with the spirit of what Luke tried to found is essentially an arm of the Galactic Alliance. There are probably others that feel political entanglements are the wrong way to go, and work as solos, or "rogues." Jedi ronin, if you will. I can imagine a more fundamentalist approach too; a Jedi theocracy that tries to recreate the Old Jedi Order, and administers an entire state. I can imagine that followers of Sith traditions probably exist (although the "rule of two" has probably been long-abandoned seeing as how disastrous it proved to be when Darth Vader killed his master and then didn't ascend into his place) as well as other dark Force traditions or camps.
Anyway, at the moment, I'm thinking more of keeping it fairly open-ended, with lots of potential things to do rather than having a single, obvious antagonist. That certainly makes it more attractive as a setting for gaming, anyway.