the thing is USF actually doesnt need as many options because their important units unlock rather quickly and they can handle a variety of situations with the units on hand. riflemen are quite strong throughout the early and mid game, and they can continue the aggression with lts and light vehicles, where as okw has relatively easily beaten units in the early game and then struggle to get out relevant vehicles. the majority of their DPS is focused around the sturmpioneers which can be focused down pretty easily by the more numerous rifles, and as paula mentioned rifles beat volks grenadiers pretty much all the time on a 1 to 1 basis.
there are two issues with the faction design. one is whether they are interesting or not. USF is boring as fuck for the first couple minutes because, non-doctrinally, they have 2 infantry and a support unit. OKW i find less boring early but they're boring for a lot longer because their reduced fuel income means they have reduced access to half their rooster.
the other is balance. USF has a lot of problems with suppression early on but i agree that once they get t1 there isn't anything they lack counter to until med tanks start coming out. OKW has some problems with suppression, particularly maxims in garrisons, but they have a much more balanced early game than USF. OKW can be very strong, provided they make the right purchase with their first set of fuel and don't lose the vehicle.
tl;dr: USF is very boring to play early game but teching covers the gaps in early functionality. OKW is not as boring to play but has a harder time covering the gaps in their early functionality.