I'm a little confused at how the Marshal believes others are demagogues, yet he runs a totalitarian regime. Does he have an unironic complete lack of awareness of what he's doing?
I ask because in my study of various real world dictators, notably Mao Tse-Tung and Stalin, they pretty much seem to know exactly what they're doing. They might tell other people all sorts of stories about so-and-so being evil, but it's gaslighting / propaganda. They know they're all playing the same game with people's heads, and that it's about power. This became very apparent to observers as Stalin was climbing to power, when Politburo meetings were becoming ideologically strained, with all sorts of rubbish uttered just to paint someone else badly for a day or two. Then the completely opposite views would be held next week! All just words; smarter people more interested in survival, recognized the posturing for exactly what it was, and kept their heads down because Stalin was going to be the winner.
As for the gameplay, doesn't -5 PLANET mean you cough and the whole world floods? Particularly with Genejack Factories to egg it on.
A Punishment Sphere driven society is an interesting idea. People can neither be unhappy nor excel. In my mod I deliberately made the spheres cheap and available early, as torturing people to keep them in line really shouldn't need any special arrangements. I might use them for distant cities, if I'm not obliterating everything.
As for naming suggestions, I don't have anything specific yet, but I do have some thoughts on thematic relevance.
"Unity" is really off the mark. This faction is exactly the opposite of anything the Unity mission stood for: squabblers are wrong, only the Marshal is right. "Unification" or "Unifying" might work better, and would definitely be a kind of doublespeak. It also connotes a cult to some of us, because of the Unification Church, so that may or may not be a reason to use or avoid it. My instinct is to stay away from "unification / unity" words and find something else, but I wouldn't pronounce final judgment on that, in the absence of anything concrete.
"Army" is a bad choice. The Spartans do an army, that's their schtick. Your faction is about genetic control. Way back in the days of Gamma World, one of their factions was the "Knights of Genetic Purity". I'm pretty sure the acronym was meant to resemble the KKK, although who knows maybe also the KGB. That's not an explicit suggestion, that's just an idea of where genetics and eugenics might lead you.
All this war with Planet implies a lot of terraforming. "Earth First" is a phrase that immediately leaps to mind, as to what the political consciousness of this faction might be like. "Earth Makers". "Originalists". "Homeworld". I'm imagining a sort of Earth nativist movement, rather explicitly racist and speciest. Sort of thing Donald [Sleezebag] might like to be in charge of, but worse. "@#ck Planet." "Make Earth Great Again!" "Planet is a @##thole."
The Eugemony?
They're not doing Evolution though. They're doing the opposite: Intelligent Design. So I don't think evolution or evolutionary is on the right track.
"Gene Stealers" is an image that comes to my mind, sorta ala Bladerunner, but not appropriate for a faction name.
Making a Speeder or Hovertank predefined colonization unit is trivial in alphax.txt. The trick would be making it only available to 1 faction.
The faction could still trade away this tech to other factions. You can't stop them from doing that. So strictly speaking the idea of a faction-specific unit does not exist in SMAC, like it does in other games say Civ III forwards. But you can definitely have a faction start with a kind of unit that others don't start with.
That's my biggest problem, will the AI be too stupid to use colony rovers even?