Am I the only one who'd like the game to take place in China?
They are the other half that caused this entire situation and I'm sure we bombed them as well. Sure China back in those days didn't have certain landmarks but a fully communist country with tons of people living within it. Imagine the Chinese wasteland and feral ghouls numbering in the thousand chasing your characters through a Chinese settings. Also China isn't America so less guns and more melee/bow and arrow type combat. Better yet it could be a post apocalyptic version of some of China's folklore. Theirs a fine line between mutations and mythical creatures that can easily be crossed. Heck that one cartoon Adventure Time made and entire TV show about that as all of those mythical creatures are just evolutions of hideous mutations that happened after a massive nuclear war that pretty much wiped out humanity. The entire cartoon is post apocalypse so why not do the same here by having them turn Fallout into an Elder Scrolls in a post apocalyptic world.
If not China then the question doesn't become one of where for me but when so location aside if the next Fallout was still in Murica' then I'd like one closer to when the actual bombs hit. When maybe some of those computerless vehicles were still in operation. Who knows maybe it could be your characters transformation into a goul that drives the story.