What if the the margin was there to compensate the lack of mine, rocket arty, heavy tank, elite infantry etc...
All other factions have access to at least one of those without having to use a doctrine. And even if you take doctrines in account, don't forget that other factions also have doctrine granting them the same amount of bonus.
I'm not saying the situation is ideal but you can't really be serious with this argument. Other faction's margin is in what they can field around their tank destroyer USF can't.
Ostheer margin is in the pzwerfer behind the panther firing at Jackson's support troops so the panther can freely roam around.
etc...
since you mention it. USF has now very good indirect fire consistency. Scotts, pak howies and mortars, not even mentioning the good MHT and also "the best heavy TD to compensate" the game is basically unbalanced. Sin the only viable counter for jacksons is infantry AT and those are *humm *humm not cheap at all, and they are easily -no micro needed- indirect fire. Its a lategame domination because counters (inf) are countered before they can damage frontline units.
Lets do a checklist before jumping to conclusions
USF:
-Lategame infantry control *using riflemen + indirect fire units (mortar, pak howie)
-Lategame tank control *using M36s
-Lategame indirect control *scotts, Priests (doc)
Seems pretty solid. What about axis
-Lategame infantry *Obers (?, vetted volks or pfussies
-Lategame tank control *JT (doc), Eleph(doc)
-Lategame indirect *MHT (doc), LeFh (doc), arty call in (doc)
It seems that doctrinal solutions are a must, but USF has stock full potential lategame arsenal, because it "is compensating lack of mines"