I only ever played 1941 before this game, and the main difference (besides the politics and others) is the fact that China can rebuild itself.
I agree with what you say about industrial complexes, and besides building some in mainland Asia, there are few areas in Global 1940 (only Egypt, any continental European territory for the Allies and I can’t think of any others for Italy and Germany, maybe Yugoslavia).
I only see industrial complexes built a lot in side switch versions, such as this:
This was one of my first posts, and there’s lots of discussion about other house rules as well.
If it’s not said there, when ANZAC sailed and captured a lot of territories in the Middle East they built quite a lot of industrial complexes, which the Soviets then captured. Allied Japan also built a major industrial complex in Korea, a death sentence for the Soviet Union. Still wishing to play this version again sometime.
I hope your Global 1940 game goes well!