In the meantime here's a case study. It's my current game and we've just finished Spring 43. I'm the allies.
The Western Allies have taken all of North Africa and have just invaded Sicily.
The Pacific map shows that Japan failed to secure Burma and the Japanese have retreated to the Burma-Thailand line. But in Winter 1942, the Japanese damaged three of the five American carriers and so have regained naval superiority which they have (under)exploited to contest the Solomons.
feel free to comment on how you think the different sides are doing