I wonder how much difference there really was between the members of the SS and the Wehrmacht. The western Allies were very keen on rehabilitating the Germans once it became apparent that the Soviet Union had been emboldened and empowered by its victory in the war. So lots of white-washing by way of histories, biographies etc. of Wehrmacht officers.
The actual situation as far as world view, adherence to Nazi policy, etc. is somewhat more murky. The Air Force was always the most 'national socialist' of the German services, the Navy retained some its Christian heritage and the Army was somewhat reactionary. Even so, far more Army commanders were adherents of Nazi racial policies than might be suggested from post-war accounts.
Not wanting to paint with broad brush, though worth noting that even the officers like Stauffenberg who opposed Hitler were not necessarily opposed to a Germany-over-all worldview. Stauffenberg, for example, was apparently thrilled with the result of the Polish campaign, and he is recorded having made anti-Semetic comments and approving of the notion of turning Poland into a slave-state of Germany.
Trying to understand the 'average German' may be a fool's errand, not because you would have to generalize over 90 million people, but because our own frames of reference have changed so much, directly as a result of the war.
I liken it to our strict no-smoking rules in public places (which I happen to favour). It's surreal now to see photos or film of people smoking on airplanes, in restaurants, etc. and we're at the point of wondering how and why they would have ever done that in the first place. So it is with the Germans' relationship to others in the 1940s. I think the average Wehrmacht troop (naturally, with exceptions) held ideas of racial and national superiority that would have come natural to him (and probably relatable to by Canadians, Americans, Brits of the 1940s where institutional racism was still practiced), but are repugnant to us today.
There are some good books about the myth of the 'clean Wehrmacht' representing more recent scholarship than the period of white-washing may have permitted.