I would rather pay for a Sino-Japanese war mod.
Every time I mention that theater people just say "LOL RAPE OF NANKING". What about the Battle of Shanghai? Or Xuzhou? Casualties on both sides were massive. The variety in the Chinese forces would be HUGE. You've got nationalist troops(most of whom wore German uniform, without German insignia of course), communist troops, various warlords etc etc. Not to mention the amount of weapons at their disposal. The Chinese used any weapons they could find.
Too much variety, actually. With so many warlords (Yen Hsi-shan and his locally-produced "Type 17"--a .45 ACP copy of the Mauser C96--backed up by locally-produced Thompson 1928 SMG clones, is probably the most famous given the Type 17's appearance in the
Metal Gear Solid series) and the fact that China was split amongst the Nationalists (today reduced to a "rump state" on the island of Taiwan) and the Communists, you'd end up with too many sides with too many weapons to balance.
By comparison, both the NK and Chinese forces in the Korean War largely used Soviet-supplied weaponry, the models and animations for which have already been produced by TWI for HoS and can easily be ported over.
It's be pretty cool if each map for the mod focused on a battle relating to each country (not just mostly focused on one or two countries)
Different battles, different weapons, different vehicles, different tactics.
I think that'd be pretty epic.
I promoted the idea of an official TWI-developed expansion taking place in a Korean War setting precisely
because they've created so many of the needed assets already (in both HoS and RS), which should ease the development process. Expanding into British Commonwealth nations and other UN nations would increase their workload. Mind you, I'd certainly
like to see British Commonwealth forces (the Short-Magazine Lee Enfield Rifle in particular, since it held 10 rounds in its internal magazine and its bolt-action could be used in a rapid-fire "mad minute" fashion), but the best chance an official expansion would see the light would be if they made NK/Chinese vs. SK/USA maps first, as it would be the least risky/expensive option.