I don't think there's any one person with the powers of an emperor in the TEC, or Trade Order, as we've decided they're two separate things, right?
I think there would be something like a committee of people, can't remember the word for some reason, who run each planet, a committee above them to run a region of planets (around one star), a committee above that and so on and so on. All elected. Things would still be streamlined because the committee on the planet level would focus on its planet issues, the system committee would focus on things the affected the system as a whole, as so on. Each group could give an opinion for an action that is decided by another committee, but they have no real say in any matter that goes beyond their committee's power. So instead of an emperor-type person, there's a committee of about 9-19 people (keep it uneven so there's never a tie) who discuss matters for the Trade Order as a whole. That would include a liason to the TEC heads (no name for them yet), who manage the entire war effort. Either way, nowhere is there a single person with all the power. There are groups that decide everything, and there are time restrictions for every issue so that no branch gets clogged up with a mountain of issues. They have say a week to decide on an issue of this importance, a day to decide on an issue of that importance, and a month for an issue of so-and-so importance. Do you get what I'm trying to say?