I'd rather have the three factions than the suspicious hivemind. The latter is smart, strong-willed, has a head for tech, and doesn't trust us in the slightest, making it very dangerous. The factions, in contrast, will have a harder time getting to a point where they could likely be much of a concern, and the group most likely to be able to make interesting tech is also the one least likely to do anything to us, and the fan-auths could likely be relatively easily put to heel. The only likely troublemakers are the fan-mils, who... are neolithic.
I don't care how advanced their tactics can be due to their cleverness, sharp rocks are not going to cut it against Astartes unless you get a psyker.
Personally prefer 3 factions.
Factions +1
I figure a cunning, distrustful hive mind is a lot riskier than a bunch of Stone Age factions.
Stone weapons can be surprisingly effective
Factions if only because Iron Will becomes nearly meaningless if there's no individuals, and because one xenophobic hivemind seems much more difficult to get on our side
+1 to factions
The Xenos are broken into
three broad "factions" in their neolithic society. One
Fanatically Militaristic and
Egalitarian, one
Fanatically Authoritarian and
Militaristic, and one
Xenophilic, Pacificistic, and
Materialist. The first two are locked in a bloody struggle to determine what means of rule is necessary to guide their species forward, tribal democracy or strongman chieftainships. The egalitarians were the initial aggressors but the authoritarians have grown increasingly stubborn in the face of the threat they pose. Because their species doesn't require agriculture to survive and uses minimal resources, this conflict is purely ideological and driven by an iron-will, it isn't likely to end any time soon. The third is content with either and would prefer peace but have settled in different regions. Something notable about the Xenos is that unlike humanity, they don't have a nomadic past, due to their photosynthesis, they are content to remain in a small area perpetually. Their spores have nonetheless seen the population scattered over the planet.
If they were left alone for millennia, it's likely they could've reconciled their differences over time and moved on to do great things. Now that they're in the Chapter's sight, that's not likely to be happening any time soon.
There's only one question about them left to answer.
What name do the Xenos have for themselves and what, if anything, do the Chapter call them instead?