I've had this idea juggling around of a nation of potent synthetics that, for the most part, have managed to perfectly hone the human condition---but have begun to grow weary of immortality and perfection. Rather than trying to improve, the society wants to regress backwards, in a sense learning to feel, suffer and succeed again. 

So far, it's been going well. The synthetics have since adopted a well-rounded human culture: The faction will be modeled after Earth---specifically the US cultural fashions and aspects of the 1950s, with several planets named after big-time US cities such as Chicago, New York, Las Vegas, Detroit, and Washington. I'm debating whether or not these planets should, in fact, be megastructures, such as a series of ring worlds.