Yes, this is the issue exactly. I don’t care about undermining or reinforcing the systems in this CG or anything like that. It’s the overall narrative that doesn’t make any sense.
An imperial faction is under attack by external powers, any other imperial faction should help. They’re all part of the empire after all. Maybe you don’t get merits for the emperor for killing archer ships but you certainly shouldn’t get merits for destroying Duval ships. Wouldn’t helping Archer take territory from Duval undermine the empire overall? Like I said, doesn’t make any sense.
For that matter there shouldn’t be any outright violent hostility between minor powers of the empire where you’re blowing up ships of other imperial factions. How in the world is that not considered treason against the emperor? It just seems like the empire (and all the other major powers) are in an open state of civil war.
If these things don’t change then the only thing that makes sense is to, as you say, get rid of the superpowers in the narrative and just have a bunch of minor powers fighting for control. It makes no sense that Patreus, Duval, Torval, and the Emperor are even considered a single empire with all the infighting that’s happening. And Patreus is supposed to be the admiral of the imperial fleet? How does that make any sense when his forces are outright blowing up the Emperor’s ships. This is not a serious narrative.
It's one Empire, but have you considered that Arissa Lavigny-
Duval and Aisling
Duval would be rivals in a power struggle? The Empire is fractured and has been close to civil ear on more than one occasion. AD has some ideas that are considered very unimperial and Torval openly hates her, for a start off.
Patreus and Torval are probably powerful enough as Senators that more support, they could have a crack at the Imperial throne if traditional lines if succession are going to have the rules bent as they have been already.
There's also been a few instances where ALD's hold on the throne has been found to be more tenuous than you'd think. It was only a few years ago she had to have senators executed summarily on the senate floor itself for supporting the Marlinists as a show of strength.
What you've probably got is something similar to the courts of rulers of medieval England. Everyone supports the ruler officially, until they have a chance to have a shot a gaining power for themselves.
As for how we'd get away with murdering ships of powers without those powers actively hunting us, I'd point you in the direction of that pilot's federation license. The same thing that allows you to get away with everything, so long as you pay off the right people. After all, just because you pledged to a power, doesn't mean you're under any direct command structure.