This topic was a bit talked about in several other topics (Bronze Age Expansion or https://forum.ancient-cities.com/t/ceramics-and-pre-pottery-neolithic/3502?u=louis.mervoyer)
However the purpose of this topic is to gather the different ideas at the same place and talk about gameplay mechanics and possible implementation as historical realism has already been address in other topics.
So my point of view:
Village specialization is something that can really add flavor and replay ability to the game.
The idea is simple: each field (farming, hunting, fishing, livestock, metal working, pottery, weaving, building, etc…) have levels (hidden) and the more your tribe practice a field the better they become in that field. Each level can either unlock a new building, increase yield or trade value.
Example livestock: level 1 small herd, level 2 selective breeding (more meat), level 3 cheese (new building), level 4 less aggressive herd (medium herd size), level 5 selective breeding (trade value of living livestock increased), etc…
The effect of a level can also be chosen randomly among several options.
That way the player can take advantage of the environment: flood plain near river => farming specialization, clay area => pottery, sea or large water body => fishing and boat building, etc…
As the surrounding villages also specialized it can be interesting to trade with them (or loot/conquer) because even if you have the same goods, the quality is different. You can have basic farming and livestock but high level pottery or metal that you trade for food.
That way, with each play-through you can choose a different specialization and increase the lifespan of the game.
A bonus: migrants could randomly arrived and improve a specific field by several levels (ex: skilled potters)
I also think it should apply to construction as well. It would be weird to be able to erect a huge menhir if you never done it before (start small).
As time pass the level of all fields could slowly increase.