I could see it as part of a Tetrarchy type system. For periods during the Roman Empire there wasn’t a single Emperor there were 4. A junior (Caesar) and senior (Augustus) emperor for the Western and Eastern empires.
The Roman Empire’s government had two major related problems. It never established a stable and reliable means of succession and because of that the Emperor couldn’t delegate major problems to anyone else because that person would become a threat to overthrow the Emperor. The Tetrarchy was an attempted solution. Two emperor’s would share power and have junior colleagues that they could delegate tasks to who would eventually succeed them. It didn’t really work out and only lasted about 30 years before Constantine made himself sole Emperor.
The Terran Empire would clearly face similar problems with regards to succession. I could see an Emperor setting up a system where a junior Emperor was chosen by the Hunger Games method. I also wouldn’t expect it to last.
The Macguffin of the story, the Godsend, was a built by Georgiou as a deterrent against anyone trying to overthrow her. She says there were always plotters and coups.