It's almost as if we are seeing Marianne's story through Elinor's eyes. I say almost because I think that is simplifying it too much. S&S is not one person's story at all, imo. It's almost a study of human nature, but JA doesn't use generic or stereotypical characters to build this study. Her characters are intricately developed and multi-faceted. I do think although JA changed from her original title, the story is still about Marianne and Elinor.