I'd relook at the numbers there. The Soviets had a 3:1 superiority over the Axis in the East in Summer 1942 and a slightly better than 3:1 superiority by November.
The US in 1942 got insanely ASB lucky at the battle of Midway, which seriously changed the naval paradigm in the Pacific for the rest of the war, while in the land fighting the Japanese were badly overstretched in the island campaigns. At Guadalcanal the Japanese were outnumbered 2:1 on the ground.
I am sort of the expert on Midway, Wiking. The Americans had no luck at all, not even in the decrypts which needed massive additional un credited Australian help (FRUMEL) to pull off. In air operations, Miles Browning probably KILLED more American pilots than the Japanese did, playing the part to Spruance what that incompetent flag signals officer did for Beatty at Jutland, when he botched the battlecruiser action. America's "luck" and it was not luck but skill, was having Spruance fix Browning's mistakes and having a competent Fletcher as an added insurance pad to bring off the dive bomber strike.
As for Japanese operations in the Solomon Islands which I am plowing through now in another thread; the Japanese barge war operations kept them competitive clear to Christmas on Guadalcanal. Too many people confuse the Guadalcanal air garrison with the line marines when touting combat noses on Guadalcanal island. In the front lines, the numbers were infantry even. And by front lines, when I add the air war, I include the Rabaul air garrison. There the Japanese HAVE SUPERIORITY.
Russian front, south the point of contact equation appears about the same. Here the Germans actually helped the Russians out with their Caucasus round trip to set up Stalingrad, but the mistake not-withstanding, the Russians needed skill to pull together the logistics required and they needed skill in the fighting troops to make it work. I don't take Mannstein as gospel any more now that we have the Russian records. The Russians were with their backs to the river, their mass de maneuver was too far north and they had to do some fast and fancy two stepping to move it to meet the German threat at that time and place. In February 43 it was 2 to 1 after the Germans were corked. Not in October 42 when it mattered.