Nice list. I especially agree about the ghost army--too convenient without any foreshadowing, and then so overpoweringly awesome that it seemed a little cheap. As I recall, their role in the books was more of intimidation in order to capture the ships rather than to charge off them and completely destroy everything.

I was a little disappointed that the Witch King was so much more powerful than Gandalf. I suppose the idea is to paint the battle as truly frightening, even for him, but really I think he as Gandalf the White feared only Sauron.

The matter of ring ownership is pretty well understood, I thought. I think the movies conveyed it exactly as Tolkein had spelled out in his books.

All your other points are well made, and I share in most of them.