Remember this is for one battle per leader, but it is a decent idea. Aldertag has the starting disposition correct and it contains all types of commanders.
Russia: 1 General
Germany: 1 General, 1 Air Marshal
England: 1 Air Marshal
Japan: 1 Air Marshal, 1 Admiral
America: 1 General, 1 Admiral
Now if you add Italy, they have 1 general ( Rommel)
Give UK one General
If you add anzacs they get nothing