On a somewhat related note, I think corporations need to become less powerful in terms of their output. Making the AI realize how much you gain from resources if you have many corporations is already a good step in that direction, but in many cases the power of corporations also comes from large territory and acquiring resources through that.
In BtS this is partially balanced by corporation upkeep, which I obviously don't want to bring back because of their semi-random spread. However, stacking up resources is currently doubly beneficial because it both attracts corporations and determines their yield. Maybe their effect on the former should be drastically reduced or even completely removed, making infrastructure more important and spreading corporations out over the world more.