I don’t think Japan is too strong.
Well, ofc., compared to its historical counterpart, yes, but not in the balance of this game.
If the Victory Conditions would be 14 instead of 8/6, the allies would win all the time, so no, Japan cannot be too strong.
With the VC set to 8/6, both axis powers are too strong because the allies must focus (the USA its income) on 1 axis partner in order to achieve anything meaningful and, with much less to nothing from the USA, try to prevent the other from winning at the same time.
The allies are always able to achieve meaningful victories on the map they’re focusing on (so also on the Pacific map), but the axis power that is not getting the heat is then skyrocketing into someting uncontrollable, and then they will get their required number of VC…
The way I see it now is the USA has 2 options:
1. Focus on Japan. Japan will then quickly (within ~7 turns) be reduced to 50-60 IPCs income, at which point the USA must refocus to Europe, to prevent a German win. If they don’t (refocus), the allies will crush Japan into oblivion, but loose the game on account of German successes in Europe/ME/Africa. If they do (refocus), this will enable Japan to make a comeback and in the end, the allies end up way behind in economic situation, achieving nothing.
2. Focus on Germany. The Nazi’s advance east (all into the Middle East) will be halted after turn ~7 or so, and the allies will crush them. Japan however, will win on the Pacific. Nothing the allies can do against that anymore. In order to prevent this loss in the Pacific, the number of turns the USA can focus on Europe is very limited. Only 2, maybe 2½, but that’s about it. After that the USA must refocus on the Pacific again. So much for Germany first, but if timed and calculated very precicely, the allies may have a small window of opportunity to land in Western Europe and if they can land without being thrown back at once, this usually heralds an allied victory. I can’t stress it out too often, that the landing must be calculated and balanced very carefully because otherwise it fails. This is very hard but in short it comes down to buying only as much escorts as needed (depending on the German airforce) and the rest transports with men and equipment. Lots of transports. Also with the UK. The allies need at least 11 or 12 transports (total togehter) to make a landing during turn 4 (more if forced to land turn 5 because of whatever axis delay-tactics…). This is when Germany has invested a LOT into the Luftwaffe and the allies are forced to buy more escorts for their transports. If Germany has invested more into troops and keeps them west, the allies will need even more transports…
Maybe there is another option that may be the solution to the allied problems of late, but I never tried it because I always assumed it cannot work: spread the US’ s income evenly between the two maps… I very strongly assume this will not work, but if some1 thinks otherwise, please come out ;-).