It’s so curious, and frustrating, that they wrote Belle into the Snow Queen story, Anna’s story, then they put her to sleep as the curse played out. Possibly she won’t ever be part of Anna’s story as she leaves Storybrooke and returns to Arrendelle. Anna could have given insight as to how Rumple was involved with her parents, the hat, the sorcerer, etc. I would have loved to see Anna react to learning her friend Belle actually married Rumple.
Also frustrating that Belle actually saved Robin and Marian’s lives, but she has no part in their present stories. She had a fairly significant backstory with Robin when he broke into the Dark Castle, but they don’t interact in Storybrooke.
And Henry, working in Rumple’s shop. So much potential, but…..nothing happened.