So, I kind of have two ideas. One is maybe having some sort of father daughter moment between Ava and Hiccup(whether it me dancing with ehr father like they woudl when she was a child, it be just them having some sort of a talk, or something else. I think it'd be sweet. (and if the moment isn't them dancing, I would love to see Ava and Blizzard(maybe Ava dragging him to do it rather than it be of his free will) dance at the bonfire(maybe Hiccup starts the dance with Castiel with the Dancing and the Dreaming and it get everyone dancing :3 ).
My second idea is having the fact that Ava will one day be Chief(chieftess) and maybe with that having either her not wanting to be it like her father was when it was first brought up by Stoick, or have maybe Calder having some jealously about her maybe one day becoming leader of the village since it was thought during all her years of disappearance he would one day become chief?