@beelee haha yeah I mean I guess you can tell why I'm always trying to duck out on this part, cause the noodling takes forever and my backwards brain and penchant for mistyping is a particular struggle. 
@wc_sumpton
Love it!
So one of the ideas I had, which I think still holds promise, is to develop a map that could service basically 6 standard WW2 scenarios by year/start date. Each of them would likely have some unique issues that may require some suspension of disbelief or re-balancing acts to get up off the ground, but basically 1939, 1940, 1941, 1942, 1943, 1944. I think these could be developed simultaneously, taking some pressure off the individuals scenarios, since we could develop them in tandem. 6 may be biting off more than I can chew, but it's a D6 game, and I kinda suggested a production spread from 1-6 PUs, so I liked the symmetry on that.
Then for a final scenario something more stand alone set in 1945, but which introduces fantastical or sci-fi elements for the X files treatment on WW2. So introducing Aliens with Flying Saucers, Mutant Zombies or Super Heroes, Giant Kaiju type monsters or things of that sort. The reason being that I think it would be very hard to create a compelling or satisfying game with a 1945 start date, since the war is nearly over and that's basically at the end of the tech tree. So instead of having a situation where we have everyone shooting Nukes at each other, or instantly into a Cold War WW3 game that lasts into the 1950, my thought was that when Trinity happens, that's what calls down the Aliens. Or opens the gates to Hell, sets off the crazy mutations or whatever, and we can basically get an A&A zombies style take on things, but with more freedom there to mad experiment. Or to rebalance the gameplay around novel mechanics, while being less beholden to history but which can play more into a War of the Worlds or Village of the Damned sorta vibe.
I don't know that I'm nearly as invested as I should be in any one given sort of game, I just really like the idea that we might have a nice skeleton with some sturdy bones to build on, which is also relatively simple to deconstruct or transform for other purposes like the idea mentioned above. Ever since AA50 came out with multiple start dates, I've been intrigued by the concept of multiple scenarios using a single catch-all map.
For China, I agree it can be a bit problematic, because they use different rules than all the other playable factions in A&A. I think an ideal handling would be, instead of creating specialty rules for just 1 nation, that the China rules or something similar might apply to any Nation that has their capital sacked. So like after they get robbed, that a nation might continue to be a factor that way, spawning infantry similar to the way China does. So in a G40 style, perhaps France works that way. Or perhaps if Moscow or London is captured, that faction could still spawn Inf units using the Chinese method. Something similar I think could work for say the 1917 Revolution, if adapting the map for a WW1 type game.