Honestly the Deus ex Machina thing happens a lot in his films, I felt Spirited Away pulled the same stunt with it's ending. Of Miyazaki's personal films, I feel Ponyo is one of his weaker ones, though I still enjoyed it. Of Studio Ghibli in general, I feel Tales of Earthsea is the obvious weak link from the studio as it never felt like it really had a point while trying to do too much.

Howl for me simply had a great cast of characters and I felt that what it took from the book it was based on, it did a great job with. Howl's setting really feels like a setting taking right out of Miyazaki's imagination.