First when I've read the preface I thought Edward would became bad... or something like that.

the perfect ending for ME would be, when the volturi do a brain-washing on edward or something, after the married and the honeymoon. Then he want kill jacob. but in the last moment bella protect jacob and Edward bite her unwanted. he realize it and become good again. then bella is a vampire, and NOW she can became pregnant and jacob print on Elizabeth (NOT renesmee,like the mother of edward)
otherwise it's the end to happy and without barrier like all twilight-series books!!!

and I'd like more Bella and Edward moments !!!