I am a detractor and I struggle to figure out how Rose cannot be the weakest character in the movie. With the exception of her first scene, where she is established as a naive true believer (which is partially dropped as the movie seems to take her side for the rest of the time), every major scene with her makes no sense. The two worst lines of the movie "Not fighting...." and "Only one thing gets you this rich...." are from her. It seems like the conversation takes it as a given that she is worse than the rest of the movie, regardless of how good you think the movie is.
Also I have never seen a coherent defense of the character as not the worst thing in the movie (and yes this is an invitation to give me one).