The Twilight story, as I understand it, is far from finished. In fact, it seems like Breaking Dawn was just the setup for what the true ending is supposed to be.
Renesmee’s very existence is the ultimate disturbing revelation: Vampires and humans can be one and the same. Do you have any idea what that implies? It implies that there’s no reason to believe vampires and humans cannot coexist. Renesmee is proof, because she is literally half of each.
This changes everything for vampires. Everything! The entire vampire population, especially the Volturi, now have to seriously reconsider what the world will look like for the rest of time. Do you really think the Volturi went home at the end of Breaking Dawn and were just like, “Okay guys, let’s keep doing business as usual!” I don’t think so. No chance.
In addition to the heavy implications that come with Renesmee’s existence, there is the Volturi themselves. Aro has openly stated he wants the powers of Alice, Edward, and Bella for himself. Even if he didn’t want Alice’s foresight, Edward’s mind-reading, and Bella’s immunity, there is still the fact that these powers all belong to a single coven – a coven that was prepared to resist the Volturi. At the very, very least, Aro would need Carlisle’s coven destroyed just to ensure the Volturi remain the most powerful.
Keeping on the subject of the Volturi, my favorite character in this universe, Marcus, has some serious unfinished business with Aro. Marcus is 3,000 years overdue to learn the truth of what happened to his mate. It is stated that Marcus had the greatest love there ever was, and he lost that love. Not only was his lover the biological sister of Aro, but she was murdered by Aro himself. Aro did this because they were both thinking about leaving the Volturi, but Aro wanted Marcus to remain so badly that he killed his own sister to guarantee Marcus would remain.
In conclusion, the storyteller in me knows that the Twilight story is not finished. I don’t even like the main series – I’m only a fan of the worldbuilding – and even I can tell that Bella and Edward’s story is incomplete. The entire vampire world’s story is incomplete.