The USF only have two things to research in their T0 while the UKF and Soviets have 3. Giving the USF something to research that solves their MP bleed and reliance on munitions is also a really good idea. One of the below upgrades in the U.S.F. would help the Americans scale with the British power creep.
Motorize Logistics Upgrade
-Reinforcment of infantry requires 20% less Manpower and occurs 35% faster
-costs 250 MP and 50 fuel
Prioritize Supplies Upgrade
-weapon rack upgrades cost 25% less, abilities 30% less
-250 MP and 50 fuel
Defensive Tactics Upgrade
-Owner's territory takes 25% longer to be uncaptured by the enemy
-150 MP and 25 fuel
Offensive Tactics Upgrade
-enemy territory is uncaptured 25% faster
-150 MP and 15 fuel
Great concept; all factions could benefit from upgrades like these.