The film is helped with amazing casting and a lot of care over the script. However there are things that were changed that do not matter and done for the right reason, such as Arwen being given more screen time (not quite a sausage fest as it was before), Glorfindels role in the Black Rides bit, but also bits that I really didn't like, such as messing with the power levels of Gandalf and Witch-king during their confrontation.

This lead to the abomination that is the Hobbit adaptation, partly because the film studio wanted to add an Aragorn to it, despite Thorin being nothing like Aragorn, and adding the three way love triangle because people liked the expanded Arwen story from LotR.