The other thing is the flexibility to Max/Min either economy or Military
Barborossa of Greece with Fascism as an example has the power to go 8!!! Military Policies. That is a lot of Boni
. This doesn't include the Wonder(Alambra?) that gives another military policy. If you are about get into a big war, that sounds awfully tasty
. The number of known policies atm is limited but if you are at war you might as have ALL the Boni
When the boni all synergise with what you are trying to achieve then it doesn't really matter if their is diminishing returns so to speak. It still is improving your odds at achieving your objective. If i had 8 Military Slots and you only have 4, assuming parity in tech and number, my army is Better and probably i will win