"I don't agree that "the main theme of all [Miyazaki's] films" is "the unpredictable psychologies of kids separated from their parents" - I can see this applying to Spirited Away and maybe My Neighbour Totoro, but Porco Rosso? Princess Mononoke? Nausicaa?
I'd say a more universal theme of his films is man's unconscious corrupting of nature.
I'm looking forward to seeing this but it doesn't excite me the way recent Miyazaki films have."