Pretty much all 4X strategy games take the Civilization approach to city facilities (a list of buildings constructed at a city) and I feel I've got a better idea.

So instead of having a list of city facilities the player must build the correct facility in the city radius. So say you need a vehicale factory to build a rover and in most games you'd just build it (aka add to the list of city facilities) and then start turning out rovers. My idea would require the player build a vehicle...