The High Command didn't like Shouty McTwatburger, because he thought he knew better than them. The book Himmler's War, by Robert Conroy, is a decent 'what if.' Hitler is accidentally killed by a lost bomber simply dropping it's ordinance, so they could make it back home. Himmler takes office, cuts Goering out of the loop entirely, and things spiral from there. Of course, the Allies eventually win, but the drive across France was a lot more painful. But, for best results, use 'If The Allies Had Fallen.' Because, the authors used actual historical fact (gasp), documents, existing conditions, and documents for analyzing situations. For example, 'what if' Churchill had been killed in the Taxi incident. I like it because it has fifteen different authors, all with vastly different backgrounds of study, from economical, to military.
Himmler, Goering, and I forget the other. Goering was the 'official heir' to Germany, but everybody knew the lying, addicted, pompous PoS couldn't lead a Shit Trench Detail. He, after all, said, 'We don't need the Army to break through to Stalingrad. We can resupply them from the air.' And, his infamous 'no Allied bomb will ever land on Berlin.'