Every change or addition was a downgrade in terms of consistency, feel, plot integrity, characterization ... it was really a remarkable, though dubious, accomplishment.
Faramir's decision to take the Ring.... it makes the moment that much stronger when he releases the hobbits.
It's a joke. An abrupt turnabout of the sort that only happens "in the movies", literally, in this case.
While Elrond wasn't as fatherly to Aragorn as he would have been in the books, I think his role overall was carried well.
I hear they have Michael Richards lined up to play him in The Hobbit.
I don't mean to demean Ian Holm, but I think his good representation was brought on by the fact that he wound up playing so limited a role in the film's grand scheme.
His ACTING. It's called GOOD ACTING.
[Jackson's] adherence to the original spirit of the story
Again, we differ. The look and feel was outstanding, but so many essentials of the characterization were changed or misunderstood -- and not for the better -- that the movies, despite the classic source material, were considerably less than classic. For that I blame Viggo Mortensen and Peter Jackson, principally.
Sam Raimi would, I believe, inherit the look and feel of Middle-Earth but vastly improve everything else.