You suppositions about "non-Germans" are more than a little flawed. I'd be interested to know how one identifies "the average non-German." Certainly many people believed, and still believe that Hitler was a madman, and with good reason. I have no reason to believe that most people believe that Hitler was either not human nor "Satan" in disguise. I consider it completely reasonable to assert that Hitler went into politics because he longed for power--whether or not that equates with an "insane hunger for self-aggrandizement" is a subjective judgment, and once again i see no reason to assume that you can read the minds of "average non-Germans," never mind being unable to define such a creature. I seriously doubt that he went into politics for a chance to someday kill millions of people, nor do i believe that most people believe that--once again, you have a nearly insurmountable burden of proof.
I seriously doubt that most people believe that the Germans were "sado-masochistic weirdos." As for thinking they were better than everybody else, that was a key tenet of the NSDAP philosophy--that the Germans were a master race. It was contingent upon the maintenance of such a belief that millions of people were eventually murdered. That is not, however, any reason to assert that people believe that Germans were "sado-masochistic weirdos." Given that you have no basis for such a claim, that idiocy about Americans and British being justified in killing German civilians won't wash, either. The United States Army Air Force practiced daylight, precision bombing. Their record of accuracy was damned good, it exceeded their minimum standards. That there was "collateral" damage, that civilians were killed, was a regretable consequence of a war which the United States did not start. The Royal Air Force practiced night-time area bombing, and that certainly did target, knowingly target, German civlians. I don't see any reasons for you to allege that the British considered themselves to be morally justified in doing so because of some deeply flawed character of the Germans. If one were to surmise, the most likely reason was simple revenge. They hadn't started the war, and the Germans visited night-time area bombing on them. When troops went in on the ground, they didn't round up and shoot Germans as being "sado-masochistic weirdos."
Whether or not German complaints about their situation from 1919 to 1932 were justified, it is human nature to complain. The entire Versailles Diktat myth was bullshit, as was the stab in the back myth. What the Germans complained of was almost entirely a product of their own actions in the Great War. Once again, leaving aside the idiotic claim about "the average non-German," i don't know of any wide-spread belief that Germans had nothing to complain of from 1919 to 1932. In fact, the myth that the Versailles treaty "caused" the second world war in Europe is prevalent, giving the lie to your assertion.
Perhaps you could enlighten us as the basis for these claims about "the average non-German."