Did you see my suggestion? I think it might have been missed since it's at the very bottom of the previous page.

How about we use a unique setup for Britannia games. Each nation gets a randomly assigned ally they can win with, secretly. This is done by the Admin. They are still free to ally and do diplomacy with anyone, but in order to win they must do it either solo or with their designated ally. This will stir things up a bit for sure.