Hi all, sorry if this question isn't for this sub. I just finished Ken Anderson's "Hitler and the Occult", which sets out to disprove Hitler's Hollywood created relationship with the Occult. It gives a good breakdown against these myths, but really reinforced Himmler as a culty, supernatural type. I'm just interested in reading more about his (in sure heinous and shocking) view, about his refurbished castle, etc.
The book that goes most in-depth about Himmler's worldview is Peter Longerich's Heinrich Himmler: A Life. Exhaustively researched, it gives a very in-depth view into Himmler's beliefs and the context in which he expressed them. It will hit all those things that you are curious about (and more!). I would also recommend Heather Pringle's The Master Plan: Himmler's Scholars and the Holocaust that looks more specifically at the Ahnenerbe, an SS organization that was devoted exclusively to pseudo-scientific research. The book looks at the wider context that fed into the supernatural beliefs that Himmler and individuals within the Ahnenerbe held (and acted upon).