reading some books i found that rtw and mtw2 uses the slave feature wrong. i mean if you enslave a city you get trait that increases the population. this is wrong because the slaves were not citizens so they didnt count in the city population ..slaves were used mainly to work on mines and in agricultural activities. can you make it more realistic
so i suggest this .
if you enslave a city you (may) get the trait .with this trait a special building is become availiable ,only in one city
( slave market) that give you some benefits
+happiness
--law
+ % bonus in mines (something like this has been done in chivalry total war)
+% farm income
in history without slave (specialy,greek,roman and eastern civ) the cities couldn't faction
i hope you understand a bit what i mean