A central theme of the Star Wars franchise is the eternal conflict between good and evil, or in Star Wars terms, the light side and the dark side. The heroes are always part of the Rebel Alliance, or whatever the equivalent to that organization is at that point in the timeline, while the villains are usually leaders of the Empire (or again, whatever equivalent has now come along in the story). Basically, every story within the universe revolves around the Rebels fighting against their mortal enemies the Empire with no real room for gray areas in between.
However, Star Wars could really shake up their storytelling a bit if they focused on internal conflicts within the Rebel Alliance. The organization is always portrayed as wholly good, with only the purest of intentions and the goal to end the evil rule of the Empire and bring peace to the galaxy. While there's nothing inherently wrong with this, and it works in a majority of the Star Wars movies, it would be really interesting to see a shadier side of the Rebels. Surely not everyone who called themselves a part of that group truly had the best intentions in mind, and it would be such a compelling story to see the inner workings and conflicts that would be present in any organization like that.
In general, one of the things the Star Wars franchise suffers from is reusing the same storylines over and over. The movies and shows start to get old because they just keep retreading the same ground instead of innovating and finding some new angle to come at these stories with. They have such a vast and expansive universe to work with, and yet it feels like fans only ever get to see one side of it, and in the most basic terms. Characters aren't as complex or morally grey as they could be, and instead, it's like everything has to be simple, and morality black and white.
If the stories are always going to focus on the Rebel Alliance, maybe they should make the organization more interesting than just the pure symbol of moral goodness that it always is. It's not like it has to be totally shifted and suddenly become a den of villainy or anything, but showing the cracks and division amongst even the good guys would be really interesting and actually pretty realistic. Of course, there would be dissenting opinions and infighting in a group like that, and there had to have been some people with less than pure intentions that made their way into the collective.
More than that, it would be interesting to explore potentially negative things that occur because of the actions that the Rebels take. They're always involved in a war, and there are surely innocents who have been hurt along the way because they got caught in a battle between the Rebels and the Empire. Maybe not everyone in the galaxy sees the Rebels as heroes and some are critical of the impact they've had because they've still caused destruction in some way. It's similar to how the Marvel universe started exploring the harmful impact that the Avengers had on the world while also saving it. Both can be true; the organization can be good but also do bad things and accidentally hurt people along the way. That's a much more interesting thread to explore than the Rebels just simply being the good guys and nothing else.
There could even be plots about the Rebels having shady dealings with people and businesses in order to acquire certain resources that they needed. It might be similar to the themes brought up during the Canto Bight scenes in The Last Jedi, where war profiteering becomes an issue. There are people in the galaxy who benefit from the conflict, and both sides are investing in weapons technology, so there's a lot of potential there for interesting ideas to explore. Maybe there are some people who have a vested interest in keeping the conflict going who are involved with the Rebels because they stand to make a profit from the continued fight against the Empire with the Rebels' need for weapons.
Star Wars has so much potential to explore much more complex stories than they do and to actually lean into the dark side of the light side. While the clear distinctions between good and evil can be important to have, especially in media that's primarily meant for children, it can get a little stale when the franchise has gone on for as long as it has. If Star Wars wants to explore more mature, adult stories, they need to start getting into the grittier side of the galaxy, and not just pretend that the good guys are always perfect angels with no skeletons in the closet. People still want heroes to root for, sure, but there's also a lot to be said for the benefits of complicating those character dynamics just a little bit more.