Yeah, that would be interesting, but it kind of eats into other abilities (like Maya or Dido). But I do think they could certainly elaborate a little bit on how government plaza and diplomatic quarters function. Maybe it should be something like a sort of axis of control between those districts and governors. So, say, any city not within 10 tiles of either a palace, DQ, GP, or established governor gets like -10% to yields (or maybe simply -1 or -2 amenities if you just want to tie it into those mechanisms), as a sort of "stability" penalty. Of course, that means you're more likely going to delay your diplo quarter until later in the game for put it in a strategic spot, but I guess that would also be an interesting tradeoff to consider there.
