If he had become Fuhrer, he'd have probably not been as hard-headed about stupid strategic moves like Hitler. He'd have probably let the Generals run the war and probably hold off murdering the Jews until he had plenty of Slavs to do it for him.
It was his own arrogance that killed him. Ne never varied his route to and from work each day, he always drove in an open car, had few bodyguards, and thought nobody could touch him.
One of the reasons he was cruel and brutal, was the rumors his enemies spread about him, that he was part-Jewish. To prove himself a "true Aryan", he was more brutal than the normal Nazi.