Heavy SPOILERS for The Rise of Skywalker throughout.
Star Wars: The Rise of Skywalker was billed as the finale of the decades-old sci-fi saga, and for the most part, it fulfilled that promise, with the Final Order being defeated and the Rey-sistance bringing peace to a war-torn galaxy.
But it wouldn't be a franchise movie if there weren't any threads that could lead to a sequel, and even though Episode IX is a good place to end things, it contains several batons that Episode X could feasibly pick up and run with.
Characters like Rey, Finn, Poe and Jannah may still have more to offer the Star Wars franchise, and there are also some questions surrounding Palpatine, the Final Order and the Force that could be expanded upon in the future.
Although the Skywalker saga has been brought to a close and that tenth episode is currently not in the works, there's always a chance that Disney could decide to revisit characters and story points from The Rise of Skywalker in a hypothetical Episode X, and they have many options available should they choose to do so.
8. Cleaning Up The Remnants Of The Final Order
The opening crawl for Episode VII mentions that the First Order rose "from the ashes of the Empire", with the implication being that even though Vader took down Palpatine and the second Death Star was blown up, there were still hundreds - if not thousands - of Empire staff, soldiers and engineers strewn throughout the galaxy.
And that makes perfect sense. Think about how massive the Empire is - it produced two planet-sized weapons in a matter of years! It's not like their entire force was wiped out when the second Death Star went boom, and the scattered remnants of the organisation coming together to build something new was an inevitability.
All of this in mind, it's highly likely that something similar would happen with the remains of the First Order/Final Order, which could be explored in Episode X. Based on the fact that the First Order crafted a weapon that dwarfed the Death Star and the Final Order built an insanely powerful fleet of Star Destroyers, they're clearly huge organisations, and will have lots of pockets of support in various corners of the galaxy.
And what are these pockets going to do? Just sit there and accept defeat? Probably not. The Final Order is so impossibly big that there are bound to be enough people left with the power and the willingness to rebuild it, and all it would take is a few rich officers making a few more of those Star Destroyers... and chaos would ensue.