I'm all over the map. One thing I'm consistent with, though: plant the third and fourth GP, and let a puppet city work it. You probably shouldn't be getting a fifth, but if you do, okay, spread with that. I highly recommend going to the World Beliefs screen and understand what everybody's beliefs are. It's not an automatic given that you want to spread, nor that you don't want to be spread to. The Catholics may want to spread Jesuits to you, and that's just fine with me.