----Treasuries can be built more than once in the same village, increasing territorial flexibility.----
Then you should grand extra building slot in treasury city . Now is difficult to build all necessary buildings and if we will need to build second or 3rd treasury in order to get next treasury slot. Then treasury village will be only warehouses granaries and treasury ?
And this only increase lack of kings now in RU5 there is 100kings and 2000 governors, you wont to make what in one server will start 10-20 kings and most governors without kingdom ?