I don't see any reason to say that featured leaders would be unlikely leaders, without suggesting radical sociology deconstructions. They all have intelligence, knowledge, expertise, charisma and some historical group affiliation, generally. In particular, each is amenable in different ways to imagining special devises for holding social power.
By that line, perhaps Diedre is the most likely leader, since she is a powerful psychic (game text has many mentions of Diedre's psychic conversations with planet, commentary on psychic power, and so on) enough so that mindworm captures are possible without prior planet exposure. Psychic power under some conditions could be influential. Cha Dawn also could be psychic, although perhaps individual ideology would make domination/influence impractical (if not for other psychics).
Lal and Morgan are already leaders, the first diplomacy (ostensibly strategic active political actuarial work, with emphasis in culture), the second similarly with emphasis in research and development, blatant power. Yang probably would be discussed similarly.
Svensgaard could be some kind of survivalist, or eccentric engineer. Perhaps while in space he speculated what would happen if calamity, as happens in the smac storyline at planetfall, struck the ship obligating use of escape pods, and further more, if some calamity befell escape pod landing thrusters, obligating hard aquatic landings, and an eventual need to survive in any arbitrary body of water. Perhaps as a hobby he rigged up one of the escape pods. Or anything. Perhaps he was an engineer, rigged the escape pods anyway, and no one cared because he was their engineer or escape pod use was not a concern (thwarted confidence).
I'm not sure about Aki-Zeta. If it is all about the consciousness, why have a leader? And anyway, how do they have that before mind machine interface? Optionally, many of the technologies discovered on planet could be already known, though perhaps reconstructive experts died in the crash along with computers, archives.
Reading the introductory fiction for the series, Zakharov's pretty much the only faction leader who actually does anything useful. While everyone else is busy arguing about the chain of command, he's the one fixing the ship so that everybody doesn't die.
It extends beyond that, though. I mean, they're going to an alien planet where they'll constantly be put in situations where doing the wrong thing will spell death for them and everyone around them. The people in Star Trek were all scientists for exactly that reason. "Shoot it with a gun" or "Just buy them off" or "Convert them" doesn't work on borderline supernatural physical phenomena.
If I had to choose faction leaders, I would go
1. Zakharov
2. Skye
3. Santiago
4. Yang
5. Lal
6. Miriam
7. Morgan