It would be really hard to make a good miniseries on that book. And it would kinda be racist as fuck, too.
Not saying it CAN'T be done, because it could.
Honestly from the trailer it looks like they've fucked with it too much. It was an extremely subdued story.
1/2 of the entire book was told from the perspective of that one Japanese guy. And that's a really important perspective to have in the story. And I didn't see it at all in the trailer. And they didn't even picture the I Ching... which is what PUT the man in the High Castle to begin with.