About an hour into this fifth and final film of The Twilight Saga, director Bill Condon, screenwriter Melissa Rosenberg, and (most importantly) producer Stephanie Meyer have an epiphany that is about three and a half movies overdue. There are no more undecided voters. There are no more converts to be won. They could make another five movies and those who scorn the series and ridicule its fans will line up to scorn and ridicule each successive iteration. Faced with that realization they do the only sensible thing they can do; they stop trying to expand the franchise's circle of fans and start playing to the base they already have.
Giving the base what it wants means, among other things, a more active and participatory Bella. Kristen Stewart may or may not be the most accomplished of the three lead actors—I certainly think she is—but Bella is unquestionably the most interesting of the principle characters simply by virtue of being the only one who is not static. Where Part I of Breaking Dawn's 2-part finale relegated Bella to sitting on a couch and being pregnant, Part II opens with Bella unleashed. She is in many ways as powerful as Edward, she has powers that are indispensable in a final battle with the Volturi (a coven of vampires out to destroy the Cullens), and she is acting as mother to protect her newborn child.
Playing to the base also means remembering, a bit late but not quite too late, that Twilight is supposed to be, first and foremost, a love story. Breaking Dawn—Part 2 manages to have its cake and eat it at the same time by deviating from the book in order to include a big, CGI battle scene but managing to do it in such a way so that the battle is neither the climax nor the violation of the books' core that fans watching the trailer might have feared it would be. The ratio of fighting to conversation is still too high, but the film does not abandon the latter altogether, and it manages to have a few nice character moments in between those building up for war.
Breaking Dawn—Part 2 still evidences many of the weakness that have plagued the franchise throughout, the chief being a mode of storytelling that tends to tell rather than show. Nearly a dozen characters are either newly introduced or reconvened, leading to lots of expository speeches about who has what power and why each character is fighting on which side. For those completely or mostly ignorant of the books, the last film is probably the most accessible simply by virtue of the fact the motivations of mother and father trying to protect their child is easily comprehensible and allows viewers who might otherwise need a score card to tell the players apart to easily separate the good vampires from the bad vampires. Even so, it takes the film a bit too long to realize that almost all of its set up is superfluous. The Twilight saga has never particularly excelled at world building—it has some big ideas but it almost always explores those ideas through character interactions rather than plot developments.