One thing that bothers me is how holding one luxury, like furs or gems, has the same game value as holding 20 of them. That is, if your civ has gems resource, there's no point in grabbing another unless on that rare occasion you can get an AI to want to buy it. Holding a second source of a given lux doesn't make my civ any happier or make it that much more money. If I'm selling ivory to France, I can't get them to buy more ivory.
This is even worse in strategic resources. If I'm buying one oil from a neighbor, that seems to be fully sufficient to handle all my petroleum needs. There ought to be an upper limit on how many combustion-engine based units you can build and maintain for a given quantity of oil resources you're buying. Most of the wars of the 20th century wouldn't even have happened if a single oil resource had been sufficient for the needs of any empire regardless of size.
This is even worse in strategic resources. If I'm buying one oil from a neighbor, that seems to be fully sufficient to handle all my petroleum needs. There ought to be an upper limit on how many combustion-engine based units you can build and maintain for a given quantity of oil resources you're buying. Most of the wars of the 20th century wouldn't even have happened if a single oil resource had been sufficient for the needs of any empire regardless of size.
nice!
