AAP40 strongly favors the Japanese. The Japanese have a stronger initial force, the central position and the ability to open the war with a surprise attack. The Japanese can defeat their foes in detail. Another problem is the political rules, which are overly complex and require much errata.
Political Rules You can't enter land areas controlled by nations neutral to you or sea areas adjacent to neutral land areas. Otherwise, neutral forces ignore each other.
- Turn 1: Japan and China are at war. Britain and ANZAC are allied. All others are neutral
- Turn 2: Japan and China are at war. Britain, ANZAC & Netherlands are allied. Japan & France are allied. USA is neutral.
- Turn 3+: Japan at war with USA, Britain and ANZAC. USA, Britain, ANZAC are not allied. Dutch East Indies & New Hebrides are absorbed by Britain. Indochina is absorbed by Japan. US receives wartime income.
These rules reflect the complex political situation in 1940 & 1941. Note that Commonwealth forces can reinforce the Dutch East Indies on turn 2, but can't collect income from them (or build bases) until turn 3. The same applies to Japan and French Indochina. Unlike the original game, the British don't need to occupy the Dutch East Indies with land forces. These rules are simpler than the original rules.
Surprise Attack On the first round of combat, in the Japanese turn, on turn 3, non-Chinese allied units do not make hit rolls.
A simple way of showing the initial Japanese attacks
Stacking No more than 10 units of the same side may end a movement or place units phase in an area. Bases and industrial complexes do not count for stacking. Fighters scrambling on defense and land units on transport do count for stacking
This rule reflects the logistical difficulty of concentrating large forces in small area. It also makes is more difficult to capture victory cities.
Extra Chinese Units Place 1 Chinese infantry in every Chinese-controlled area left vacant in the printed setup.
Historically, the Chinese contested the interior cities vigorously
Facilities Bases, Complexes and AA Guns, all are taken as losses in combat, and defend at 1.
This reflects garrisons and eliminates the ahistorical ability to capture them intact
Defensive Scramble Fighters at Air Bases can scramble to defend adjacent sea areas, regardless of whether the base is an island.