Economic

I thout when the cities grow bigger i would get more money out of them specially when i have all buildings that give more money, but i get lesser and lesser money the more people that lives there.

with cities with 20k+ in population i usually have -2000 income from it and after i let the rebels take over it and burned the people in there i get around +3000 dinari from the same city (around 5000 people left).

do anyoen know why its like that? with less people there couldnt be that many that can pay tax, work and trade.

Look at your management scroll. Your large city is indeed making more money, but the larger your city the greater amount of money that is earned is dished out to soldiers, family members and agents. The extra income is less than the extra amount of money that is taken out of your city's coffers to give to the government-employed soldiers, agents and family members, so on the surface it seems that large cities make a huge deficit, when they don't.

Yeah, the big cities sub the rest of the empire...