1 inf/hv inf unit - division - (17.000 men's) - OK it depends on nation but OK, Soviets inf division count 6000-8000 men's
1 eng/commandos/specials unit - battalion - (300-700 men's - OK) OK
1 tank unit - regiment - (about 100 tanks?) 100-200 depends on period of war, Soviet used tank brigades ...

OOB is the best Strategy game ever.
The best Strategy game ever = 1/3 OoB + 1/3 Panzer Corps + 1/3 Germany at War - Barbarossa 1941

That actually does sound pretty good. The customization mechanic in Germany at War (allowing a certain customization of units by adding various battalions and ...