There are multiple opportunities here!
The basic US infantry, artillery, tankers, and paratroopers in the North Africa, Sicily and the early Italian campaigns were basically the same, so a "Mediterranean" campaign series would cover a number of bases from Torch through Husky to Avalanche.
US infantry, armor and paras, British infantry armor, and paras, Free French troops, including the Algerian Goumier mountain troops, Poles, South Africans, Kiwis. Later one could add the Brazillian expeditionary force. Italy was a true ALLIED effort, but after early 1944 was overshadowed by the ETO.
I know that Andy isn't into repaints, but some vehicles could be done as North Africa (tanks with white turret stripe, or mud camouflage) or SIcily (the 2nd Armored Div used sand bands over OD and a number of vehicles had a yellow circle around the white star). Many of the basic vehicles didn't change much over the first year. US stuff would include early Shermans, Less for North Africa, early M2 and M3 halftracks, "hard cab" GMC trucks, jeeps, etc. Artillery could include the little 37mm "pop gun" AT gun, up to the massive 155 Long Tom (with a Cat tractor to pull it (used before the "proper" trucks and tractors became available). For North Africa one could even do the M1918 French-type 155mm howitzer and the M3 halftrack tank destroyer.
Required movie watching: "The Story of GI Joe" which follows a US infantry company from North Africa into Italy.
Capitalron - not a bad idea. How did any orginial thinking come out of Washington?
Gary