problem with the demand by cities is that all industries produce the same “goods” so basically if i want to run trains to the steel mill, refinery and sawmill i already need to supply 9 large cities, with only 22 cities on the large map we can only serve 6 industries. that does not bode well for industry extensions in the spirit of the cargo mod.
also the fixed supply chain dependency means that it will be even more difficult to keep production up if there will be more layers added to the supply chain. i originally had the idea to create mods to extend industries and goods so that for example from coal and ore raw steel would be created at the steel mill in the form of slabs, coils and blooms, which in turn are turned into profiles, pipes, sheets and stainless steel at various different industries which again are demanded by automobile factories, construction companys, trading companys and so on. that however is impossible at the moment because a steel mill would always turn 1 ore and 1 coal into 1 of all three kinds of raw steel, instead of only producing the one that is demanded and as long as there isn’t demand from all further layers then the production wouldn’t even start at the steel mill even though there was demand for one of the products.