I’m sorry I have to correct you. The Imperium has almost no similarities to the Holy Roman Empire it is too centralized the Imperial guard, Administrative, the church and Admech are all central organizations they are not local they all can dominate planetary governors. The imperium is closer to Ancient Rome or Byzantium, or even the Nazis or the communists than it having similarities to the HRE.
No, it is not. What you wrote may be like it in
theory, but in reality Imperium doesn't and cannot really care much beyond the planets providing resources necessary for functioning of the Imperial administration and military.
Also, Holy Roman Empire also had central organizations. It had a "central army" - in fact, it had
TWO central armies, the
Imperial Army and the
Army of the Empire. But even these forces were in fact decentralized in their structure, much like Adeptus Astartes and the Imperial Guard are.
And yes, Imperium would be able to dominate individual planet. But again, much like HRE, realities of the communications and message and army travel times mean that centralized control is impossible. And it is not much like Roman or Byzantine Empire either: I don't think either would have tolerated a territory such as Ultramar existing within it.
No, in the Imperium things might not be centralized as much as they'd like, but they are standardized to a such an extent that it compensates. Note that they have classifications for worlds based on their economy, and every world really operates the same way: there's a governor (never elected), PDF, Adeptus Arbites, Imperial Creed, etc. Basically everything works the same way, and rigidly controlled. There's very little freedom, individuality, ability to prosper, etc. It's a shit way to live.
I have already explained that before, but since apparently nobody has read that explanation... no,
there is no standardization of worlds within the Imperium. What there
IS, however, is
categorization. That is, Imperium takes a look at characteristics of a certain world, and then classifies it according to its internal system. And yes, worlds will develop in certain directions over time. But there is no case where Imperium itself decides to actively remodel a world so as to make it fit a certain category. Closest to that are Forge Worlds, but this is merely term for worlds controlled and developed by the Adeptus Mechanicus - which is, in essence, a political entity that is in federal relationship with the Imperium, rather than being part of Imperium in the way that, say, NASA is part of United States administration.
Also, everything you have listed are, again, administrative categories. Yes, there is a governor - but governor's duty is merely to ensure the world fulfills its obligations towards the Imperium at large. Other than that, governor doesn't care or can control how the world governs itself. Also, governors can be appointed, hereditary or elected, so even in that there is a significant variation. Yes, there are Planetary Defense Forces - but beyond the common moniker, they have absolutely nothing in common, and each world is left to develop its own PDF in ways that fulfill said world's requirements. Hell, even Imperial Guard Regiments differ from world to world (just compare regiments from Cadia, Krieg, Catachan and Praetoria), let alone PDF. Adeptus Arbites do not enforce laws: they merely punish serious transgressions against Imperium (e.g. rebellion) but each world has its own laws, customs, judicial procedure and so on, none of which Arbites have anything to do with. Imperial Creed is religion - that is like saying that Western Europe was a homogenous authoritharian empire during Middle Ages because it was 99% Catholic. And Imperial Creed itself is far more diverse than medieval Catholicism would have been willing to tolerate.
If you want to claim that "Basically everything works the same way, and rigidly controlled. There's very little freedom, individuality, ability to prosper, etc", you will need to do a lot more to prove that claim.
