Smith isn't an idiot though. He knew Himmler's wife was basically spying on them, and the dinner with Himmler showed killing him would be fairly easy.
I don't mind the Japanese leaving. The show needed one major victory, and they didn't have a ton of territory. They already showed the princess leaning to withdrawal anyway. Tagomi got killed (even though not by the BCR), then the meeting with the Admiral and the BCR went sideways and they were having court marital hearings. So in the larger context it was getting to be a mess to hold on to the territory, and *then* a huge oil pipeline got blown up, and Robert's telling Kido that the BCR is relentless and they're never going to stop. So maybe a little more development of all these threads, but in this season, the Japanese leaving was ok for me.
I don't think the show ending with the USA being totally free would have been earned so I do like Bill throwing down the medal. I think as someone mentioned earlier here maybe that showing a lot of the American nazis deserting and taking off their arm bands would have been better.