This...isn't anywhere near overhyped; in fact, even with the Oscar, I'd say it's underhyped; it's simply amazing, on almost every level. Character development, myth, plot, wonder, and catharsis.
And while, like every Miazaki film, it has an environmental subplot, in this film, it remains a -subplot-, rather than a "message" pounded into the ground until it bleeds, and is very well handled on a number of layers.
Now I just want to see it in Japanese.