'The Rommel was a good guy' could be said to be part of his mythology which actually dates back to ww2, when even his opponents, like Churchill purported to like him.He was also a good friend of Goebbels who helped build his mythology. He didn't treat PoWs badly, or kill captured Jews. However there is not evidence of his refusing to serve Hitler's plans, and he only became openly criticial of Nazi plans by 1944, when all was lost.
Whether serving the dreams of a monster, but not being a monster yourself is enough to protect a reputation is open question
As for the Marshall Plan, if the Soviets hadn't taken Eastern Europe and and kept a vast army waiting, it is impossible to say if the US would have given as much aid, keeping your allies from starving is different from rebuilding them. At this point it becomes counter factual and a What if scenario.