This is a more general question that can be relatable to the main game of Ancient Cities.
As we all know, with the begginings of society and civilization, mankind started to enslave fellow man.
Often slaves were acquired as war spoils. Man were used as mine and agricultural beasts of burden, and women were sold as domestic and sex slaves.
I believe in the spirit of making this game accurate and more revolutionary that a slavery-war-economic system to be applied in the game, as it would make wars and raids much more rational and a strategic decision to be taken, aside from the historical perspective on it.
Best wishes and best regards.