Proposal: City-States can't build Refineries
Refinery: provides +1 Iron, Coal and Oil, can be built in up to 5 Cities max
Rationale: A City-State with a Refinery gives the additional resources also to its Ally, and this is an unnecessary incentive to ally city-states. It shouldn't be possible to circumvent the max building restriction of the Refinery just by allying city-states. It also overlaps with the Statecraft bonus on resources from CS alliances.
Refinery: provides +1 Iron, Coal and Oil, can be built in up to 5 Cities max
Rationale: A City-State with a Refinery gives the additional resources also to its Ally, and this is an unnecessary incentive to ally city-states. It shouldn't be possible to circumvent the max building restriction of the Refinery just by allying city-states. It also overlaps with the Statecraft bonus on resources from CS alliances.