In Revised it actually makes life a lot harder on the allies. Japan now has nothing better to do than attack Alaska and W. USA meaning America has to actually invest in a National Guard and a navy in the Pacific.
I beg to disagree: in Revised Japan has nothing better to do than ignore USA, built two or three factories on mainland Asia, and start rolling tanks against Moscow
I think you made a very tactical mistake here. Japan can build a million armor pieces and can NEVER attack Moscow with them, nor can they even get to Europe because you have to go through Russia to get there.
So they do, in fact, have absolutely nothing better to do than annoy America forcing America to be more honest with history and fight Japan.
Without America giving significant aid to the allies in Europe, England will have to send everything just to hold the line against Germany and prevent Russia from falling.
This in turn spurs Germany into sending only minimal efforts into Africa so they can maximize as much punch as possible to break Russia before the joint armies are too strong to break.
(In Revised.)
This of course is if Japan and Russia cannot attack one another (or pass through conquered lands of one another) until such time as a capitol falls.
I don't understand what are you meaning
If Japan and Russia cannot attack one another, it would be obviously stupid for Japan to build any factory on mainland Asia to produce tanks and go after Moscow (since it's forbidden).
However, that's only forbidden if you play with a especial rule (USSR-Japan non-aggression treatise)
If you play with no such especial rule (which is the way most players do), and allies are not playing a KJF (which IMHO is a lesser strategy than a KGF) then best thing Japan can do is build one factory on Manchuria and one on India (after taking it from the British) and start rolling tanks against Moscow; hopping that Germany from the West and Japan from the East would conquer Russia before Western Allies take over Berlin.
Do you play TripeA? If you do, I dare you playing a PBEM where you play the Axis and instead of going after Russia you go after USA by Alaska
Then I play the Axis and I go after Russia with both Germany and Japan
And we see which strategy works better (and I'm a sorry Axis player)