Believers - I'd call them religious nutcases but they are actually onto something in here. The tech progressing in this game becomes increasingly creepy to the point even i feel distaste. The cloning vats are a great example especially if you know the inner workings of the machine in the video.
The machine in the cinematic seperates females from males.
The females are grown to lay more eggs while males get thrown away and minced alive and used as feed.
Psh technology has to advance somehow.
Also if you look at text it looks like Miriam's cult commits mass suicide through a Psi-Gate or something. Also if you look at the way she behaves in game she is the most traitorous war warmongering bitch there is who brainwashes her own followers (surprise why they start with social psych?)
University seem like the best choice, they do open research (hence the low probe score) so even if they are unethical it is known about, Gaian's on the other hand use an atrocity in the form of unleashing mindworms even though it's not under the UN charter.
Morgan is actually very unethical, as long as it makes a profit he doesn't care and as long as the rich are looked after he doesn't really care what happens to expendables.
Spartans are survivalist freaks and in the story written for AC are the reason why Capt. Garland dies and the UNS Unity fails it's mission. Although they do have the nice ideal of focusing on survival so are more likely to be safe (until Deidre rapes them with mindworms)
Yang has nice ideals but they don't work out and is actually more like North Korea. Also he is 2nd in command so has most right out of everyone to be in charge.
UN is a giant bureaucracy and the game highlights the ineffectual nature of the UN as power is the only thing that matters. That being said is probably 2nd choice after University.