It occurs to me that, in a typical game, the Allies need only attack from 5 points (2 primary, 3 secondary) in order to defeat the Axis.
Point 1 (Primary): Norway
Allies take $3 from Germany, and then proceed to secure the Karelia VC for Russia. German advances on Russia are seriously weakend due to Allied strikes in Eastern using a combination of Norway/Karelia troops and troops amphibed in from UK directly to Eastern. Preserves USSR income and frees up Russia troops for other duties
Point 2 (primary): Algeria
A US initial landing in Algeria, combined with destruction of the German Med Fleet keeps UK income up during the critical early stages of the game. Subsequent small landings into Algeria can position enough troops into Africa to where Japan will not be able to fully secure it for many turns without a MAJOR effort into Africa (at the cost of other advances). Ancillary threat to Western by risk of combined UK/US strike using USA/UK forces in UK, Africa, Norway, and Karelia as well as threat to Southern Germany helps pull forces off the German Moscow advance in the mid-game, further strengthening the effectiveness of the Norway insertion forces.
Point 3 (secondary): Persia
Initially a UK responsibility, then becoming Russian as initial UK forces are destroyed Russia maintains control of Persia for the Brits, breaking up the Japan offensive along the Southern Prong, and drawing forces off the African Offesnive to increase the ability of the US forces to keep it liberated for UK. Initially trading India, then giving ground as Japan forces increase, finally trading Persia if Japan puts their major effort south. Additionally, if Japan foregoes African advances to crack Persia, the US can advance forces from Africa to create a 1-2 punch with the USSR to secure Persia.
Point 4 (secondary): Novo
The drop-dead line for Russia in Asia. Russia maintains INF presence in Novo for defense, and to counter advances in Sinkiang and Yakut. Using primarilly FIGs to add punch to counter-attacks, Russia keeps Japan from massing for a joint Yakut/Sinkiang strike on Novo, instead destroying one spearhead in either the central or northern avenue of attack, then trading Novo usign USSR forces after the other Japan prong advances to Novo.
Point 5 (secondary): South Pacific
A moderate push by the US into the South Pacific starting around Turn 4 can be a serious detriment to Japan, forcing them to spend cash on naval units instead of funding their Asian campaign. This makes Russia’s job easier in Novo and Persia, as well as allowing the US to use a bare minimum of forces for Africa, freeing up some US forces to assist with the Norway insertion.
The result of these 5 points of attack is to keep the Axis income down. Japan gains in the far east are offset by German losses in Africa and Europe. Germany is prohibited from being able to stage for a 1-2 punch with Japan on Moscow because UK maintains the ability to land a full 8 units into Europe (combined with previously landed units in Central Europe), tying up German forces, plus a small number of US units into Northern Europe to support the Brits for 1-2 punches as well as “breach and blitz” moves. Japan production in FIC, and later in India and FIC, is split between trying to break Persia, and trying to secure Africa (one or the other has to give or both fail). And valuable Japan IPC’s are spent on naval units to counter a slow, methodical advance by the US in the pacific which preserves remote UK IPC’s, and threatens both Japan and their remote high-value IPC’s.
Remember, all the Allies nees to do early on (barring dice or errors) is contain Axis income growth, and the economic might of the Allies will overpower the Axis.