It's not the germans or US that are OP, it's mostly MGs and fully kitted out guns vs basic ones. A fully upgraded bolt-action rifle can kill in a single body hit, same with scoped rifles, fully upgraded SA rifle is both much more powerful and easier to use than a non-upgraded one, the starting SMG is completely shit, in comparison to other SMGs and LMGs are just stupidly powerful.
You get to fight against tanks on either side and, from my experience, usually it's the germans with the tank superiority. Avoid them, or get panzerfausts (found in boxes on many spawnpoints) on them.