Make Stability Slightly Harder in the Late Game and Give Bonuses for Surplus Stability

In the late game you can essentially build infinite districts given you have a reasonable amount of territories attached, making stability improving districts and infrastructure pointless in the late game. It feels weird that a city in the late game can be perfectly fine without a Sewer System or Hospital. 

On a slightly unrelated note it feels like some of the most important infrastructures to actual humankind are the most useless in the game. Even in the late game schools provide like 20 science which means nothing when you have 1000+ already and with the Inventor's Workshop and Cabinet of Curiosities some of these infrastructures just feel pointless.