The Reformation changed the face of Transylvania, during this time, there was newer protestant groups going into the land. Lutherans, Unitarians and many others.
For the most part the people co-existed with one another. It was probably because in the smaller villages the villagers had one majority culture. By this meaning: in a villages of Saxons there were few Romanians, and in Hungarian village and Romanian village the same phenomenon happened there.
So what else changed during the Reformation?
The Printing Press and the ability to learn.
However, I have been to Romania once, but that was in Sofia.