IDK if even 1 IPC bonus per working Convoy SZ can remain manageable.
US 9, UK 8, Japan 7, Germany 2, URSS 1.
Well, there’s no reason we can’t decrease the number of convoy zones. The point should be to simulate a few of the most important, most vulnerable commerce lanes, not to put a convoy box in every single sea zone that saw merchant traffic. Just off the cuff, here’s another possible distribution of convoy zones for 1942.2:
USSR: Archangel, Soviet Far East
Germany: Baltic, Central Med
UK: English Channel, Central Atlantic, Eastern Med, Persian Gulf, Cape of Good Hope
Japan: Tokyo Bay, South China Sea, Java Sea, Coral Sea, Leyte Gulf
USA: Solomon Islands, Pearl Harbor, Caribbean, New York, Brazil
That should produce a less crazy income swing. If you think that’s still too much, you can relocate income from land territories to adjacent sea zones, instead of adding fresh income. E.g., Borneo drops from 4 IPCs to 3 IPCs, but the Borneo Sea Zone is now worth +1 IPCs if its convoy is undamaged.