Feudal Future: Subverted. While the runér who make up the “executive branch” of the Empire’s government might look like a feudal hierarchy from some angles, and their titles are occasionally translated that way, in practice they have much less power than a feudal lord’s theoretical powers, and theirs is not a legally enshrined hereditarian hierarchy that places them above all other parts of society (see: Fantastic Caste System). And historically, they grew up as, effectively, bottom-up-driven administrators rather than as local warlords, the old feudal model having died hard in the tumults that led up to the founding of the Old Empires.
In short: there’s a reason tying back very directly to the fundamental nature of the Imperial government why the Imperial Couple’s formal style includes the line “Chief Executive Officers of the Imperium Incorporate”, and why the fundamental power rests – strictly according to explicit contract – with the citizen-shareholders.