I dunno. The idea of someone or something trying to bring back the Sith feels unoriginal to me. We've had the Sith for almost six movies now - yes, the original trilogy had the Empire - but I'd like to see a new threat or new enemy.
The galaxy feels awfully small if the Imperials/Sith are the only bad guys out there. Even though I thought the New Jedi Order books got a little too dark/morose for my liking, I liked the basic concept: Luke Skywalker is trying to bring back the Jedi Order, there's a New Republic and then a brand-new threat comes along that's even worse than the Sith. It made the Star Wars universe feel scary and large, like there were tons of alien species and lifeforms out there that we barely even know about.
Yeah I can definitely appreciate that argument. After six movies of black-robed villains with red lightsabers plotting against our heroes, it would be kind of nice to see something a bit different. And I do kinda like the idea of an outside threat from another galaxy, and the unpredictability that comes with that.
But at the same time... it IS really hard to beat the iconic power of the Sith. Any other villain or alien threat they try to create would most likely just feel like a derivative of some Trek or superhero movie villain, since we've seen nearly
every possible variation of that kind of thing by now. And it's doubtful they'd be half as memorable or cool as the Sith and Empire anyway.
Jedi vs Sith is what really
defines SW and separates it from all the other scifi and fantasy out there, and ultimately I think I'd like to hold onto that. Plus after all these years, I'd be seriously disappointed if I didn't get to see Luke Skywalker engage in one more epic lightsaber battle with someone.