Well the new Centers of Reformation certainly leads to interesting stuff

[IIWW]

Well, if they couldn't spawn somewhere in the British Isles, that would be pretty lousy for them.

That said, having a way to prevent multiple centers from appearing in close proximity would be good.

Define "close proximity", since that could easily hurt HRE. There should be quite an amount of CoR close by each other.

 

[Xiahou Mao]

Well, there can only be three of them by default per religion, as things stand. Given that, historically at least, we have to assume that there was one in England, one in Scandinavia, and one in Germany.

If all three appear in Germany, or the British Isles (as shown in the above picture), or in Sweden, then the Reformation is going to be severely hobbled.

 

[IIWW]

But they are not random (besides the first one of ech relligion), so maybe it would be more logical to make an additional CoR for both relligion that is tied to "non-HRE country". I can't really think of a protestant/reformed country besides HRE ones and scandinavian (thus +1 somewhere else).