"And Kilcher was only 14?! We should have heard much more of her and this performance. "
Yeah, she was brilliant wasn't she -- Kilcher did get a few awards but nothing major. As for the music, which you also brought up, it was Wagner's "Das Rheingold" in the early stages of arrival, but then Malick employed Mozart's "Piano Concerto No. 23" for the romantic passages.
"A reasonably balanced view of the Native Americans i think-not sentimentalised, demonised, caricatured or too strongly idealised. "
Very true. No wonder people from various Native American communities wanted to be a part of this project.