I always like city specialization of its production. However, this design begs a question, is production specialization the only way? If yes, that means gamers do not have a choice. There should be 2 ways for us to choose, specialize vs generalization.
In the game, can generalization (i.e. most of my cities produce almost the same stuff) provide some benefit that specialization don't?
Maybe, generalization do not provide the quantity and quality of a speciallized empire; but generalized production provide great flexibility because products are always spreads evenly across the empire, so supply line is short, products are usually close where it is needed. Thus it is more tolerant to disruption of supply line.
A carefully designed pros & cons of generalized vs specialized production model is crucial.
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Another crucial missing piece from the video is that there is no mention of how 'area of control' is determined. Is it by a contest of 'prestige'?
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Agreed with Tormy that the map look crowded. And it does not have a 'fantasy' look.
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I see that there are building can be built on steep hills. Pls make sure there tall mountiains should be very common in most maps, so that there are plenty of natural choke points.