That was my guess anyway, in which some houses were sworn to the Bureaucracy or the IA.  I just had the interesting idea that there might be noble houses/governers one might need to win to their side assuming an imperial family member or another power wanted to gain the imperial throne. I imagine the more archaic feudal system might have been born from the fact the first colonies were established before proper FTL travel through hyperlanes, thus these colonies might have regressed a little technology wise. 

By the time the void was found and began to be utilized these human worlds later discovered retained little of their old technology. They had devolved into feudal states ruled by aristocratic nobles. Perhaps still retaining some more advanced technology in the form of mech/warframes used to fend off hostile xenos. That's the plan for my systems, anyway, something other people might adopt if they want to help flesh out these first colony worlds. 


I imagine these feudal worlds are more on the fringe of the empire while the core worlds are more modern in terms of government.

The idea of knights trading in their plate and horse for walking war engines is tantalizing to me. 

https://www.youtube.com/watch?v=wI7ft8xMYuQ



Now another topic I want to go into later is how the church is structured, and how ingrained is said church into the empire? Is their an oligarchy council? A head of the religion like a pope?