Like the original poster, have had similar problems, at some point end up just bludgeoning my way to Paris. Have had similar problems with frontline units. I have not been just stuffing 24 divisions in an army, have built historical orders of battle. Basically every time there is a Belgian stone wall, the one province in Wallonia, further the units attacking into Luxembourg get counterattacked which stalls the whole offensive. Most of my infantry is 20W 7/2 infantry artillery with some 40W 14/4. Motorized infantry is standard template, Panzer divisions upgraded to 6/4 the six being a mix of medium and light. The biggest problem I have had is the Allies own the air with 3,000 fighters this has stymied my last couple of campaigns. I have been reading the other posts on building industry, which I think is my issue. Have not been able to match the AI Air Force