I find it a lot harder to start completely from scratch with a sequel trilogy compared to with a prequel trilogy. Even harder to build it into a coherent story. This is more of a “Plot points, aspects, and ideas I’d think about were I making a sequel to the Star Wars trilogy”.
-When a sequel trilogy takes place has a huge impact on its story. If it kicks up a few days after RotJ, it’ll obviously be very different from if it kicks up 3 decades after RotJ, or if it takes place long after the OT trio are dead. I’ll put it 10-30 years after RotJ for the sake of this though, mostly because it just gives the ST more room to breathe.
-Feel free to ditch the trilogy format if necessary. If the plot makes more sense with only an Episode 7 and 8, go with it. If the plot needs 4 or 5 movies to tell, go with it.
-I don’t like ripping off the sequel or prequel trilogy we got, but Kylo Ren’s character is great and the meta-story is kind of something you could only really ever do in a sequel to the Star Wars trilogy. Too big an opportunity to pass up. I’d keep the villain being something like that: Starting the trilogy as being someone who idolizes Vader and wants to become him. If depicted sympathetically, he can grow out of it like Kylo does, but if not, maybe he doesn’t. I’d rather that he do, though, because that’s not a schtick that stays interesting past like, one movie. Maybe two.
-I don’t like the NJO Legends stories and I don’t like sequel rewrites that are similar to it. I don’t like the idea of Luke being at the head of a formal institution, and that being how the Jedi are brought back to the galaxy. Maybe Luke has an Academy, sort of like Plato’s academy. Maybe Luke’s first students have a sort of disciple-like relationship with him. After scouring the galaxy on as much information about the history of the Jedi, he takes on a small handful of apprentices to be the next generation of Jedi.
-Luke will also be willing to teach literally anyone about literally anything - Despite Leia, Lando, and Han being unable or unwilling to make the huge commitment to become a Jedi, they’ll have learned a lot about being more Jedi-like from Luke. They’ll be more spiritual in this trilogy. This is what I imagine from Yoda telling him to pass on what he’s learned. Taking on apprentices sure, but also spreading Jedi wisdom to the whole galaxy. All of it.
-The conflict should have roots in Episodes 1-6. An idea I like is if the Rebellion in the OT was made up of two factions: One being the wealthy, influential Senators, businessmen, etc, who just so happened to not be in Palpatine’s in-group, and the second being the common people, especially from the Outer Rim, who suffered hard under the Republic and the Empire. Once the Empire falls, the common enemy these two groups have, they’ll turn against each other.
If this sequel trilogy has to coexist with Lucas’s prequel trilogy, it could also retroactively add some depth to Palpatine’s rise to power: The flaws of the Republic made the Empire inevitable, and this ST could get into those flaws. The Rebellion was NOT an Alliance to Restore the Republic, at least not to the second group.
Making the other group more and more like the Empire also adds depth to Palpatine and the Empire.
-The main characters of the OT should fade into the background over the course of the sequels, passing the torch onto the younger main characters. At least one of these characters should be a child of the OT trio, with at least one Skywalker. But they shouldn’t dominate the story in the way that they sort of do in Legends. I think the Skywalker grandchild should turn to the dark side, being the heir to the Skywalker legacy should do that to you. Maybe there are two of Anakin’s grandchildren, though, and one could be light and one dark. But keeping the conflict entirely in the family isn’t something I’d be a fan of.
Honestly, dealing with the Skywalker grandkids is probably the hardest part, because on the one hand, a Skywalker grandkid being irrelevant to the story would be really weird and jarring, on the other, having too many Skywalker grandkids in the story would be really overpowering (If you thought the canon movies being turned into the Skywalker saga was dumb, imaging an ST with four Skywalker grandkid protagonists), and on your third hand, you have two Skywalkers who’ll potentially have kids.
Maybe Leia and Luke have one kid each, and one kid is the villain and the other is a sort of deuteragonist.
-Luke doesn’t die a virgin. Not a fan. I’d also like him to have a daughter, but I’m not committed to it. If he ever had a wife, though, she’s dead by the time of Episode 7. I don’t want to set up a Luke/whoever romance and starting the movie with him just kinda having a wife would be weird. I’m down with him being gay also, but then he doesn’t get a daughter, because I don’t want him to adopt or use weird space tech to get a man pregnant in between movies. If either of those happen, it’s happening on screen, god damn it.
-The main protagonist and POV character is not a Skywalker grandchild. Not interesting. Something I like is if they’re trained by the/a Skywalker grandchild, though.
-I like the idea of Luke being out of the picture in Episode 7, because I agree he’d be way too overpowering if he was right there from the start. He didn’t go missing, though, that’s way too close to ripping off TFA. Maybe the story begins with the/a Skywalker grandkid finding the main character, and toward the middle or end of TFA is when Luke shows up? There should also be conflict between the POV character and Luke over the trilogy, and any good-guy Skywalker grandkid(s). Luke immediately getting along with them and never having any conflict is just boring.
-The main conflict has been going on for a bit before Episode 7. If it’s between those two Rebel groups like I said before, the civil war has been going on for a few months or years already. If there’s a powerful Imperial remnant, they’ve already been the biggest issue in the galaxy for years by now. If it’s something entirely new, that war has been going on for a little while now. A lot of ST rewrites spend half of Episode 7 showing us what the new society they’ve set up (New Republic, New Jedi Order, the works), and the villains don’t really even exist until the middle of the movie. Not interesting.
-The conflict of the entire Star Wars saga ends here. There can more sagas, other sagas, but this saga ends here. And with good finality. We should trust at the end of Episode 9 (or whatever if we ditch the trilogy format) that none of this can happen again. If we’re going with the Republic vs Rebels thing I mentioned, the Rebels win and set up an entirely new system, one without the flaws that the Republic had that led to the Empire, or the suffering of the people even in the Republic. Maybe with its own new flaws, but the flaws that led to the Empire, and the conflicts in Episodes 1-3 and 7+, are gone.