Every civ can have modifier for each wonder, which of them they prefer to build (for the AI)
So, we can make it more likely that a wonder is built in it's homeland or a similar society, but I don't think we should restrict it to those
Too much wonders associated with state religion won't do good for gameplay IMO, we should leave as much freedom as possible to the players
Btw, the Shrine of Uppsala needs Pagan Shrine, so some sort of paganism is already required for it
The other wonders you mention could have been built by any of the religions, if medieval europen history works out differently
I agree on the other thing, the +50% Golden Age length wonder would be nice to be availeable to all civs.
Any suggestions on how to change the wonder bonuses?
Keep in mind that we have plenty wonders. So I don't really want to add a new one, only if it's necessary...