Unironically, Arthur Seyss-Inquart. If all other options are already exhausted and most of the old inner circle are dead, Seyss-Inquart could ascend to the top easily, since he's probably one of the last people who worked relatively closely with Hitler.
People are insane. If Speer is contained by the player's decision to go along with the Go4, that is the most hopefull outcome for everyone involved (except Speer), including whatever Russian unifier will come and reclaim the lost territories.
We're talking about months, not years here. Even with a harsher Versailles treaty I don't see the Nazis grabbing power before 1932, and in 1932 only with luck (Hitler defeating Hindenburg in the presidential election, keeping the 230 seats in the Reichstag in the November election, etc).
Yeah, no. Why should the surviving Soviet leadership surrender if they knew they'd be pretty much safe behind a line of natural fortifications and strongpoints, being aided by the rough weather and the partisan movement behind German lines? And even if the Germans marched beyond the Urals, what...
As long as something like a central leadership AND places to relocate to exist, there will be no official surrender, nor a cease fire. It was pretty evident from the start of the war in '41 that the Germans are aiming for the total destruction of not only the Soviet Union, but its peoples. That...
Really? I think the IJN would at least have developed nuclear reactors for the capital ships and submarines. Japan OTL built that many nuclear reactors to be not as dependent on oil imports. I don't see why they shouldn't invest a little bit more to keep the IJN afloat with going full nuclear there.