Hi Locarnus,
I'm unfortunately pretty underwhelming in the graphics aspect, and have not worked on western ally graphics so far.
I don't ask you to create icons from scratch, not at all.
Why not asking the permission to PaK mod creators to use the icons they use (or icons designers PaK mod uses) for British and US ground forces, then you will get Allied forces "in line" with the icons you use for Soviets and Germans.
Here we have original Pz Corps icons (a very old look) for Allied vs finetuned icons (a modern look) for Soviets and Germans, this makes the Pz Corps campaign quite weird in terms of look.
I have finished the panzer Corps campaign, the final scenario versus USA where all US units have original Pz Corps icons (excepted airplanes) : despite this graphic discrepancy, it was very pleasant.
The ability to play the original campaign + DLCs with your mod makes it outstanding (+ Battlefield Europe of Mc Guba of course).
Another question: The player can play all campaigns with your mod (AK, Soviet Corps) with one exception: Allied corps. Is it intended ? Honnestly I do not see any place on main screen to show it, so I guess it might be difficult.
Next major step is making your mod usable for Sea Lion campaign, Western DLCs and US Grand Campaign.
Maybe your primary interest is in German and Soviet units.
In AK, British units have the "old look" too. I think that using PaK icons would be perfect for Western units. Just my two cents...