There is something that makes to think that the game doesn't look like realistic war company.
Having read much about ancient wars, I think that greatest problem of ancient war company was in supplying of food and carrying it to army.
There were war companies where big army having no food was beaten by small army having good food supplying.
Other case, when attackers block defenders in a city and cut all ways to carry food into the city, then in some time defenders, having no food at all, are forced to open gates and to surrender even if they have good weapon and fortifications.
Food supplying meant so much in ancient wars, and we don't use it in the game. We pay no attention to one of mainest factor of win.
I would offer to use food supplying in the game.
Supposably details are: All units have money upkeep and food upkeep as well per each turn. Food sites are like money income buildings, they produce some ammount of food every turn. Cities have start ammount of food but they can't produce it. Special units, peasants, can carry food to armies in city or in field.
Every unit has own food fund, and when this fund has become empty, such unit can't fight (but probably can move toward peasants) until he will get food.
Such changes, at my look, can give to the game more reality and to make the game more popular in the strategy games community