Quote Originally Posted by kekvitirae
Two words: Religious unrest.
I dont like having to march in to a city only to have it (at worst) rebel in two turns because the religion was way different than mine.
I haven't had this problem so much. But I generally put big cities to the sword, leave up existing order buildings (including the church), set taxes low, and garrison heavily.

You can often tip religion in your favor and start converting with a general or two and border power. (Another trick to tip conversion in your favor: if say you're trying to convert a pagan city to christian, knock down their big pagan temple and rebuild a small one)

In a few turns, when unrest has died down (and particularly if you can get an arena up and some conversion going beforehand), you can usually safely knock down their church and put up yours.