Taking into account that 4 nations precede America’s turn, here is a KJF that seems to work (if you are looking for Slow Japan First, which is what you asked for.)
1) 6 Russian Infantry in Buryatia
2) 4 Russian Infantry, 1 Armor in Sinkiang
3) British Fleet unification in SZ 30
4) British Retreat from India to Persia
5) British Bomber to Caucasus
6) British landing in Algeria
7) American IC in Sinkiang
8) American Air Force in Buryatia (hopefully after sinking the SZ 60 fleet, if it is vulnerable.)
From here you can take East Indies with England or do massive damage to the Japanese fleet and air force attacking your fleet in SZ 30. (Sometimes I’ll take 2 Inf from India and 2 Inf from Australia to tempted Japan into hitting my SZ 30 fleet!)
Also, you can build Americans directly in Sinkiang while the russians protect you until you have secured China. (Build another IC in China with America, move Russians in to defend it.)
England can put an IC in India if it can take and hold it a round. If not, you might want to put one in E. Indies. You DO have two transports down there, might be worth it.
Anyway, the goal here is to sink the Japanese fleet primarily. Once that’s gone, you can prevent them from building a new fleet and pick up some islands along the way.
The risks are the early fall of Russia, loss of Africa, maybe Brazil to Germany, reduced income usage in E. USA/England to annoy Germany with.
The pay off is an England earning 40+ IPC and an America earning 40+ IPC with large production ability in SE Asia. (IC’s in Sink, China, FIC, India, Manchuria and maybe Kwangtung after all is said and done.) More then enough to take out Germany, even if Moscow falls.
Remember, the allies start with the money, all they have to do is keep it and take out Japan’s outside territories. Even if Germany gets Russia, the Allies will out produce them and, eventually, be able to push them back. (Defending Europe and Asia is too hard against England and America with no Japanese distractions.)