One thing which is far too easy in EU3 is converting religions. Through numerous religious decisions and a level 6 theologian I can get 20-30% conversion rates on a heathen, uncored, wrong culture province in Africa.
My thoughts are that you should not be able to convert provinces of different culture groups (except for pagans) unless you have a core there. I can't think of a time it happened; in Granada we can assume Spain had cores there, and the same with Russia in the Steppes. However, even in those places conversion was not easy.
On the other hand Ottoman Europe never converted to Islam, while British India never magically became Protestant, nor the Dutch East Indies Reformed. So even when you can do it it should take a LONG time unless they are your culture.
Conversion within your religious group shouldn't be punished in this way of course, but it should still be more difficult than it is in EU3.
My thoughts are that you should not be able to convert provinces of different culture groups (except for pagans) unless you have a core there. I can't think of a time it happened; in Granada we can assume Spain had cores there, and the same with Russia in the Steppes. However, even in those places conversion was not easy.
On the other hand Ottoman Europe never converted to Islam, while British India never magically became Protestant, nor the Dutch East Indies Reformed. So even when you can do it it should take a LONG time unless they are your culture.
Conversion within your religious group shouldn't be punished in this way of course, but it should still be more difficult than it is in EU3.