I've decided my Blindsight elsewhere fic is going to be set in the seventh or eighth millennium BCE after all. Notes on how I'll portray the humans, focusing on how I'll approach the question of war and socio-economic inequality in early Neolithic Anatolia (the setting of my fic):
Inland agriculturalists: probably the most populous local branch of humanity, and the one where most of our archaeological evidence of the first farmers comes from. Farm wheat and pulse crops, but acorns, pistachios, and figs are also important food sources to them. Some livestock, but hunting is still the primary source of animal protein for many communities. Foraging of wild and semi-wild plant foods (e.g. acorns from wild and semi-wild stands) is still important for many communities; communities often surrounded by fuzzy concentric circles of various intensities of eco-engineering rather than there being a sharp dividing line between farmed land and totally wild land. Agriculture, originally an extension of women's gathering activities, is still highly feminized in this era; men participate in farming, but a lot of plant cultivation is women's work. Inland agriculturalist gender relations more-or-less follow the hoe culture pattern.
Inland agriculturalist society is relatively peaceful and inlander agriculturalist communities are not very militaristic; to the extent that they are militarized it's often primarily oriented at defense against vampires and coaster slave raiders. Serious direct attacks on settlements are rare, so settlements are usually not very fortified; what fortifications exist are often mostly for protection against vampires and coaster slave raiders. The biggest threat to inland agriculturalist communities is the new crowd diseases being spawned by the agriculturalist lifestyle.
Inlander agriculturalist communities are mostly relatively socio-economically egalitarian. What social hierarchy exists is mostly gerontocratic; the words of elders carry weight. The inlander agriculturalist socio-economic system distributes most of a community's surplus more-or-less evenly among most of its members.
Inlander agriculturalist communities often do have leaders who are usually men and usually hand power down to their sons. However, these leaders are very dependent on the ongoing active consent of the governed to have any power, and they have about the same material standard of living as normal members of the community (though they do often possess symbolic luxury goods like precious stones and stone cups as symbols of office). Inlander agriculturalist communities do not tolerate leaders who try to tyrannize over their community or who live well while their people go hungry.
At the other end of the social scale, the other major exception to the relative socio-economic equality of inlander agriculturalist communities is, unfortunately, slavery. Slaves are mostly female refugees from the coastal zone, who are vulnerable to exploitation because they have no local social connections. Slavery is highly feminized because agricultural labor is feminized and because women are perceived as easier to control; inland agriculturalists have little interest in enslaving men (the equivalent bad end for coaster refugee men is to be killed as a trespasser or to be driven away into the wilderness and sooner or later end up as vampire food or meet some other similarly nasty fate). Slavery is not hereditary, and slaves may achieve integration into the community on better terms eventually. An imperfect but possibly illuminating recent historical analogy for early Holocene Anatolian inlander agriculturalist slavery is Iroquois slavery/bride kidnapping/adoption. Slaves are a small percentage of the inlander agriculturalist population.
Coastal farmer-fisher-whalers: probably originally a sedentary fisher-whaler culture on the shores of the Mediterranean and the Euxine Lake (what later becomes the Black Sea) which then adopted agriculture. This is a precociously urbanized, stratified, and militarized society with long-distance trade and raiding, deep sea fishing and whaling, and what could generously be called fortified city-states ruled by kings (though they're more like big villages by modern standards, a few thousand people). They're kind of like an early Holocene equivalent of Vikings (late Bronze Age Greece may be another relatively good analogy). They don't appear in modern history books because a lot of their settlement sites are now below sea level (sea levels were still lower than today during this era, especially the level of the Euxine Lake) and the ruins they left have been pretty thoroughly chewed up by coastal erosion and scavenging by later humans.
The coastal zone is much more militarized than the inland zone. War is more frequent and is often existential (whereas for inlanders it's usually a matter of disputes over things like acorn-bearing oak groves and hunting grounds on the periphery of a community's territory), so coastal settlements are much more heavily fortified than most inland settlements.
The coasters have not yet invented a social technology of territorial imperialism; the goal of coaster aggressive warfare is the capture of plunder and slaves, which are transported to the aggressor city-state to increase its wealth and labor force. A lot of this slave labor is then used for agricultural intensification. The result is a sort of Darwinism of communities; stronger communities attack weaker ones, enslave much of their population, use that slave labor for agricultural intensification, get even bigger, use the resulting increased military power to attack more communities, and so on. The main wrench in this is that these practices tend to also make coaster city-states festering factories of crowd diseases and spread those diseases around, but this tends to synergize with rather than disrupt this dynamic: faced with declining populations, coaster leaders tend to try to solve that problem by capturing more slaves. Greater militarization and boats capable of coast-hugging journeys of hundreds of miles means the coasters are also well-equipped for opportunistic slave raiding, and coaster slave-capturing parties have made themselves a major hazard over much of Asia Minor (they're basically a similar hazard to vampires; unlikely to attack a main settlement unless it's very weak, but will pick off individuals and small groups). These slave-catchers, and coaster traders and military expeditions, tend to spread diseases around as they travel, much like European explorers, conquistadors, and settlers did in the New World 1500-1900. The coaster society is a major driver of regional population movement, as the coastal zone is constantly drawing in captives while at the same time it has an outflow of escaped slaves, refugees from destroyed communities, etc. (they also indirectly drive a lot of population movement from the plagues they spread and from people moving to get farther away from them).
Big and powerful coaster city-states have large slave populations. Coaster slavery is less feminized than inlander slavery, as the coasters have more use for male slaves for heavy agricultural labor, but it is still quite feminized, for the same basic reasons as inlander slavery. Standard coaster operating procedure after total defeat of a rival community is to massacre most of the men and enslave most of the women. Coaster slave catchers preferentially target women. Unlike the inlander society, in which the social technologies of coercion are very rudimentary, coaster society is beginning to develop things like slave barracks, chain gangs, professional slave overseers, etc.. Coaster slaves often do not reproduce themselves, due to short lifespans, the gender imbalance of the coaster slave population, and the "would you want to bring a child into that kind of life?" factor, but when they do coaster slavery is often hereditary, though coaster masters have the option of acknowledging children of slaves as their own (a lot of people born into coaster slavery are conceived by masters basically raping their slaves), in which case they inherit the social status of the father; the trend is to acknowledge sons (who are more useful to the masters as male heirs and warriors) early in life when they're young enough to thoroughly socialize into the master's culture while leaving daughters in slavery. Coaster society has much higher socio-economic inequality than inland agriculturalist or hunter-gatherer society. The basic unit of coaster social organization is the patrilineal clan, with smaller and poorer clans vassalized to bigger and richer ones, and clan membership and rank within the clan as major components of social identity and determinants of socio-economic status. Patrilineal descent being important means coaster society is more patriarchal than inlander society, with coaster women having less sexual freedom and less freedom in general than inlander agriculturalist or hunter-gatherer women (the fact that coaster city-states often have relatively giant majority-female slave populations also contributes to this; the institutions and cultural sensibilities of a society like that tend to be not great for "citizen" women either).
I made up the coasters cause I wanted to set up an Alien vs. Predator sort of conflict between the vampire pack in my fanfic and a suitably nasty human proto-state; I bet that shows.
Hunter-gatherers: these are still a major feature of the Anatolian world in this era, especially in the inland northeast and in regions that aren't great for agriculture (hills, mountains, uplands, swamps, etc.). They are mostly small groups of nomads; in this region larger and more sedentary hunter-gatherer groups have mostly adopted agriculture to some degree by this time. Already in this era these people can be understood as "barbarians" in the James C. Scott sense: people whose cultures have developed in dialogue with and reaction against settled people. A lot of these people are escaped slaves and refugees from the coastal zone and their descendants, and that influences their culture, e.g. intensifying the simple hunter-gatherer trend toward "fierce egalitarianism."
----------
Both the inland agriculturalists and the hunter-gatherers have to some degree developed a cultural identity of "not like those assholes on the coast and proud of that," and this has mostly influenced them in what I and probably you would see as good directions; weakening hierarchical institutions and cultural features and strengthening egalitarianizing ones. Unfortunately, I think the flip side of that process would be making the coasters worse; it'd be anachronistic to call the coasters fascists, but I think their culture would probably have a lot of that energy.