I absolutely agree that most characters were done a disservice in the translation to film. I don't like it, but many of the changes really were driven by the medium. Why the love triangle in the second movie? Because Jackson needed some reason to put Arwen on the screen so she doesn't disappear for the middle-third of the story. Why is Faramir such a jerk to the hobbits? Because there's not enough time to explore his wisdom and goodness; instead a redemption arc satisfies the audience, and it can be done quickly because Boromir has already outlined that arc.
And this is coming from a guy who will use the intermissions to lecture his friends on what is missing from the original story.
And this is coming from a guy who will use the intermissions to lecture his friends on what is missing from the original story.