I am a fan of taking smaller balancing steps when I find out that the original game balance might be a problem. This goes for any game including this one.
At first I have to say that I don´t think the odds are in such heavy favor for the Axis side as many have written. Of course the odds are hard to quantify, because dice luck and mistakes can have a huge impact. My impression is that the Axis side may be favoured in sth. like 60:40.
What we did to keep it in a close-to-50/50 balance:
The “Closing Dardanelles” rule is a must have.
Beyond that changes on the technology chart are useful. We use different tech trees for each nation (including new technologies). Next to balancing purposes this also serves to add more historical accuracy.
In addition we invented a rule that differenciates between old tanks and modern tanks (you will need to add a model type for those old German and Soviet tanks). Japan, Italy and GB will be restricted to old tanks (attack value of “2” instead of “3”) for the whole game. Germany and the CCCP will start with a mixture of old and new tanks, but both can produce modern ones. This takes some of the “gas” out of the Axis offensive power. E.g. it might slow down Japan´s progress in Asia just a little. Same with the Axis in North Africa. And it adds historical accuracy.
Another tiny modification: We give Italy the territory of Italian East Africa as a “home territory” (because it was officially still their colony when the game starts in the summer of 1941). This gives Italy one additional IPC at the start of the game, but we also move one British infantry unit from South Africa to
Rhodesia in the starting setup. Thus Italian East Africa will fall within the first British turn and their infantry can reach Egypt more quickly.
Small modifications, but the result is a close-to-50/50 balancing. Our last game took sth. like 12 hours over two days.
It works.