Humans... or at least me... are so bad at this sort of multivariate optimization. Even if you cheat and give yourself infinite resources and all the technologies and set out to plan the perfect economy from the get-go, eventually something you forgot will throw a wrench into some tiny part of the supply chain, and the whole thing comes crumbling down. Then you try to build some redundancies into the system, but the overlapping networks create routing problems of their own.

I wonder, in general, if games like these are "solvable" via some sort of theory, or if you just have to iterate through a billion configurations before you arrive at a better one...