Some people have asked me about culture, if this is going to follow the Greco-Roman flair of Nessos or be more open ended. So there will generally be 3 major cultural blocs:
The Ancients
The Sea Peoples
The Hunters
Each of these ur-cultures will have a general aesthetic, but you can develop dialects or sub-cultures with a lot of diversity within these groups.
"The Ancients" will mostly inhabit the middle of the map. They will be late-Neolithic tribal peoples who are semi-sedentary, living in permanent or seasonal villages. They will mostly have Finno-Ugric sounding languages heavy on short curt words with vowels. (Think Finnish, Baltic, Samoyed, etc.) They are highly likely to have fertility and nature pantheons. They are gradually being invaded, enslaved, and displaced by the latter two groups, and will most likely be subsumed culturally if players do not choose to champion them. Their survival will mostly likely involve hybridizing with their neighbors, or figuring out how to organize more effectively before it is too late.
"The Sea Peoples" will mostly inhabit the south of the map, although they are rapidly colonizing coastal estuaries all over the map. The Sea Peoples have mature Bronze Age metallurgy and seagoing ships. They are migrating from a more urbanized and violent region of the world. They are not representatives of a large empire, but could represent individual groups being pushed from their homelands by climate change or war. These empty regions, inhabited only by primitive tribes, are ideal for a new start for their people. The sea peoples are generally warlike, proud and exploitative. They have complex pantheons but often worship gods who control the seas, skies, and storms. Their challenge is leveraging their technology and mobility into a permanent foothold in the land. Their languages resemble Egyptian, Phoenician, or Greek.
"The Hunters" will mostly inhabit the north of the map, although they will often descend into the center and the south on raids. The Hunters represent a great migration of tribal peoples from the center of the continent that has finally passed the mountain barriers. They are peoples on the move, at odds with each other, and organized in shamanic and martial cultures. They do not possess advanced metallurgy but they do trade for metal objects over long range trade routes. They tend to menace and coerce the Ancients, taking them in slave raids and selling them to Sea Peoples for weapons. They are an extremely unsettled people, and will migrate for long periods of time off the map area. They will often worship animal gods, war gods, and the gods of their neighbors who they take a liking to, but they are ripe for new religions. Their languages resemble "Aryan" tongues like Norse, Saka or Sanskrit.
All three of these origins can be either proto-democratic or autocratic or anything in between.
The goal of this will be to give people some flexibility, if they'd like to do a lineage inspired by the ancient Mediterranean, they can take a Sea Peoples culture, or if they'd prefer to do something a bit weirder, they can do one of the Ancients or the Hunters. Fusions of two different cultural groups are also fine. And within these categories there's a TON of leeway to specialize.