The way I have come to like the political situation in the new movies is by looking at the galaxy almost like an individual, and apply Jungian archetypes, which is often used to analyze characters in the films.
If the Old Republic was like a person, then Sidious was like a person’s Shadow. So when the Old Republic transformed into the Empire, it was like that person’s conscious self became a slave to the autonomous shadow, controlled by their more negative qualities. The Rebel Alliance was like the conscious ego taking control back, but in the end of the ROTJ, the Rebels merely purged/repressed/disowned the Shadow. So one could look at the Rebels/Republic/Resistance and the Empire/First Order as two halves of the same person, like a Jekyll and Hyde, the Ego and the Shadow.
The New Republic seemingly never resolved that problem until, after being repressed for so long, exploded, coming back even worse than before, like a soda that is shaken up and the pressure is suddenly released.
For a person to be more “balanced”, per se, they must find self-actualization or self-realization, and to do that once must integrate their shadow. Basically, someone who reincorporates the shadow into their personality, produces a stronger, wider consciousness in themselves than before. They have to acknowledge their dark side in order to become a fully realized individual.
A lot of this rests on how Episode IX pans out, but if this idea continues into the conclusion, then I would think IX would end in the reunification of the First Order and the Resistance. It sounds a little crazy, but I imagine they could achieve this theme either through Kylo Ren, who controls the First Order and could possibly be redeemed, thus reintegrating the First Order, or through Finn, who will take the lessons he learned from the last two films and help liberate the bulk of the First Order military, the Stormtroopers, from their servitude.
The lessons learned from understanding and dealing with one’s shadow is a big aspect of the Star Wars film, being represented by the dark side of the Force, and both being a metaphor for facing one’s own negative qualities, impulses or emotions. So to me the political situation, which I still could have been explained better in the films, is a continuation of those themes. And looking at it now feels like having the threat being a resurgent Empire was the natural direction to take for this final trilogy. Maybe they could have told that story in different ways, but I don’t think the way they are telling it goes against the Saga. It’s the opposite, to me, at least.