He is only frayed a bit from the Tolkien Aragorn by needing to be "bucked up" by Arwen when he doubts. The real Aragorn does not doubt and he does not waver in his intentions and hopes with Arwen. Neither does Arwen waver. They both do in the movie.
With the wavering of Aragorn, PJ just tried to bring out the mental confrontation that might have been going on in Aragorn's mind. The movie Aragorn has been shown to be weak in his mind doubting the strength of his lineage and his fate. He believes that he too is as weak as Isildur was and hence the mental battle and dilemma.
The movie gutted the character of Faramir. In the book, he is completely the man who would never take the Ring, and would be well past that adolescent angst vis-a-vis his father that the movie depicts. That whole shallow soap opera of brothers and father there functions levels way below Tolkien's world.
Faramir's character was done pretty well. He loved his brother and admired him. But then he wished his father would stop lamenting the loss of Boromir. Actually, Faramir wanted his father to see that he himself is as good as his brother. The movie clearly shows that.
Tolkien's Denethor is, at worst, proud and cold. But he is always assiduously attentive to the defense of the city and rules with strength and intelligence and seeking the good. There is a horror to his insanity. He is a loss. PJ's Denethor is downright loathesome and exhibits no particular talents, and we are not sorry to see him go.
Denethor has been portrayed as insane. But then if a character is given a screen timing of just 1 hour it is very tough to actually develop him in detail as can be done in a book in a matter of a few pages. Actually, the idea of Denethor as a power-crazed person did go down well with me since I never compared the movies with the books. Denethor's character could explain a lot of things in the movie.
Tolkien's Ents are ancient and deep with wisdom, memory and thought. That trick of Pippin's makes Treebeard little more than a buffoon.
PJ's ents too are deep with wisdom, memory and thought. Pippin's "trick" (as you call it) was just to go home safely. He obviously didn't know thet the trees had been cut at that part. And as with a shepherd, a loss of his sheep makes him kill the wolf won't the treeherds do the same thing? The Ents were brilliant.
Speaking of buffoons, Merry and Pippin are supposed to be young gentlemen and the particular friends of Bilbo and Frodo. Despite a youthful hobbitlike lightheartedness, they are far more serious and brave than the movie depicts. For instance, Pippin's swearing fealty to Denethor is respected and praised by Gandalf, but in the movie Gandalf treats him like a foolish child. Again, though, the actors do very well with what they are given.
Pippin and Merry were solely for comical relief and for moving the watchers emotionally. The movie hobbits were harmless, little creatures who had nothing to do with any of what happened and they were dragged unknowingly into the war and everything. They were portrayed as lovable beings who were at the wrong places at the right times.
Eowyn is fairly close to the book. That scene of her as a giggly bad cook is an awful degradation of Tolkien's character.
Eowyn is justified. She is shown in the movie to be a strong character as she is in the books. And then, Tolkien never wrote that Eowyn was a good cook.
The possession of Theoden by Saruman turns him into a simple pawn and replaces the terrible descent of his spirit and the potency of his redemption with a bit of fairy tale magic. Further, the king of Rohan would not ever question his duty to ride to the aid of Gondor when summoned.
I find PJ's Theoden to be more human-like that Tolkien's. Tolkien's Theoden was quite frail and was not able to take decisions for himself. I liked PJ's Theoden to be more enjoyable and brave.
Gimli has been turned into comic relief.
The books' Legolas would never express or feel the doubts and fears the movie's Legolas did at Helm's Deep.
But then the movies cannot show what a person is thinking if the person doesn't say it on screen. (whether live or in a pseudo-thought voice)
Saruman, however, is right on the money. That scene of duelling staffs pretty much cheapens the story, though.
You can't trap a wizard like Gandalf without indulging him in a fight. Well done, I say!
Other than thinking the astonishingly excellent computer graphics of Gollum never stops looking like astonishingly excellent computer graphics, I think the character of Gollum is even less of a moral actor than the book. There is a real sorrow and pathos, even hope and, eventually regret at his fall in the book that doesn't make the movie.
Gollum has been portrayed as a negative character so its obvious that people don't sympathise with him.
And Frodo sending Sam away in being duped by Gollum is completely false to the three characters and their relationships. Additionally it makes Frodo look stupid.
This was brilliant! It shows the weakening of the will of Frodo and the power the Ring had on his mind and decision-making as he approached Mount Doom. Remember, Frodo is raged at Sam when he talks of Frodo lending him the Ring to carry. It makes a good run-up to Frodo claiming the Ring in the Cracks of Doom.
On a whole, I think that the changes made in the story were made for a reason and for good reasons at that. Remember, the movie wasn't made solely for theose people who had read LOTR already. He had to include those people who had never heard of Middle-Earth or Tolkien till the movie came out. And if he had to stick true to the books. It would have taken him 10 years for all the movies to come out. Its not easy to convert a 2500+ page long story into a 9 hour movie and staying true to the book as well. He had to explain the story to everyone (including LOTR ignorants) and the only way that could be done was the way he did. I don't think anyone will be able to better the movie for another half-a-century. Its not easy to make a movie. Trust me! And its very hard to get a producer who will buy it.
If you forget whatever you know of Middle-Earth and LOTR and then watch the movie as if its the first time you are hearing of Middle-Earth, then you'll really like the movie. I completely blanked my mind throughout the movie and viewed it as an ignorant will. I never compared the movies to the books.
There's no point in blaming PJ for what he did. There was no other way he could do it and definitely no better way to do it than what he did. Kudos to Peter Jackson and the Lord of the Rings movies!