Then some comments on formations:
4.) Glider infantry battalion support 43 (unit 163)
In game terms this is a rather clumsy platoon, though it apparently represents actual support company. I would suggest changing this into actual company, consisting of HQ, MG platoon and mortar platoon.
5.) Para battalion support 42 & 45 (units 166 and 167)
These are also rather clumsy platoons in game terms, though they represent actual support companies. I would suggest changing these into actual companies, consisting of HQ, two MG platoons, mortar platoon and bazooka section (for 45 version).
6.) Ranger company ETO (unit 323)
This company is rather clumsy, with everything except mortars bundled into single formation. I would suggest splitting this into actual platoons, giving company HQ, two ranger platoons (needs new formation) and mortar section (which could maybe use formation 1255 instead of current 1346).
7.) Armoured engineer company (unit 355) and Combat engineer company (unit 356)
Both of these units have rather clumsy company HQs, consisting of engineer squad, three MG sections and three trucks. Perhaps those MGs could be split into their own platoon (Motor MG platoon?).
8.) Cannon Company 43 (unit 367)
Currently this is represented in game as a single platoon. However, according to field manual 7-37 (can be found here:
http://www.ibiblio.org/hyperwar/USA/ref/FM/ ) this company was often deployed as three independent platoons (each of two guns), typically with one platoon supporting each of the three infantry battalions of regiment. Thus, I would suggest changing this formation into a company, consisting of three platoons of two guns each (needs probably new formation for the platoon).
9.) MG support (unit 106)
I cannot think of any historical formation that matches the contents of this unit. Am I missing something, or is this purely an in-game construction? Not a big deal, I am just a bit puzzled.