Very interesting ideas. How do you represent the 20 different national armies? Do you have 20 different colors of units? Pink and lavender and light blue and so on? Do you order Siamese rondels from HBG? Sounds like an expensive house rule, although potentially a very fun one.
One nitpick is that Bulgaria seems a bit overpowered relative to history / OOB Global '40. It’s only worth 1 IPC, but you’re giving it 4 infantry, 2 artillery, and a 3 IPC national objective for Russia. I think 3 Free French infantry in Equatorial Africa is probably also a little too strong – what do the Free French have to do? They can walk into empty Vichy French West Africa & Central Africa, and then I guess start walking toward Egypt.
A more important criticism is that I think you’re missing an opportunity to streamline your ruleset. Like, yes, it’s interesting to have 20 nations, but you don’t need 20 mix-and-match sets of political and military rules. I would like to see a division between minor powers, medium powers, and major powers.
Minor powers have no independent politics or economy whatsoever, and mobilize infantry/partisans in their home territories that must stay within those territories at all times. (Greece, Poland, Yugoslavia, Holland, Mongolia, Hungary, Bulgaria, Siam, South Africa)
Medium powers can only build infantry, artillery, fighters, destroyers, and transports. Medium powers have a capital and a factory and few or no travel restrictions, but they are politically linked to a major power and cannot declare war on their own account. (Vichy France, Free France, Canada, ANZAC, China, Finland, Romania)
Major powers have a capital, an economy, no restrictions, and can conduct their own independent politics. (Japan, USA, Germany, USSR, UK).
The exact details are less important than the principle of having a handful of easy-to-remember rules instead of having a unique ruleset for each nation.
I would not bother to split up the UK, because the UK doesn’t have that much left once you split off Canada, S. Africa/Rhodesia, and ANZAC. England + Scotland + Egypt + Jordan + Sudan + West India + East India + Malaya + Hong Kong is not too much for one major power. That’s probably still less than 30 IPCs.
I would split off South Africa and Canada from ANZAC, making them three separate powers. Feels weird to lump them all together. If you want to represent British solidarity or something like that you can say that you can move up to 5 IPCs per turn among any British powers by paying 1 IPC of shipping costs.