I think the game could use a "will to fight" or "fighting spirit" capacity for each unit, to model the fact that historically some armies collapsed because the soldiers didn't want to fight. It is not the same as strength nor doctrine. Like the italian army : the italian soldiers simply didn't want to die to restore the roman empire for Mussolini or to conquer land for Germany in Russia. This could be tied to internal factors (revanchism, desire for peace) the political situation (unpopular leader/govt) the diplomac situation (the country is attacked, or is the agressor)...
A low "fighting spirit" capacity could lead to a rapid decrease of organisation after some time fighting so the player should act accordingly, rotating its division more than with another country, using mainly elite units with bonus of fighting spirit...
Some countries should start with a high fighting spirit because of deep internal factors (USSR, Germany, Japan...) and some with a much lower one (Italy, the axis minors, USA..).
Some mechanics should also represent the fact that the US public opinion can accept only much lower human losses than countries that were fighting more or less for their survival (USSR...). So a US player that sends a big infantry army overseas should have big problems at home if military defeats happens, while for USSR or Germany a defeat could even provide a morale boost to the army if correcty used by the propaganda (see Stalin'speech in fall of '41 or Goebbels "total war" speech after Stalingrad...)
A low "fighting spirit" capacity could lead to a rapid decrease of organisation after some time fighting so the player should act accordingly, rotating its division more than with another country, using mainly elite units with bonus of fighting spirit...
Some countries should start with a high fighting spirit because of deep internal factors (USSR, Germany, Japan...) and some with a much lower one (Italy, the axis minors, USA..).
Some mechanics should also represent the fact that the US public opinion can accept only much lower human losses than countries that were fighting more or less for their survival (USSR...). So a US player that sends a big infantry army overseas should have big problems at home if military defeats happens, while for USSR or Germany a defeat could even provide a morale boost to the army if correcty used by the propaganda (see Stalin'speech in fall of '41 or Goebbels "total war" speech after Stalingrad...)