Elsa-Arthur interactions? Yes, of course she wants to work together with the hunters to bring about an end to all these attacks, death to all vampires, haha... Whoops, turns out everyone lies to you, Arthur.
And if you go with the "Korra was experimented on and now has to adjust to being a turned vampire" maybe Elsa (and Bucky?) helped/hid her right after she was turned? Because Elsa's role in this AU is to run an underground vampire daycare, or something. I think that could deepen their relationship after the event ends and possibly make it more balanced, in that Elsa ends up helping Korra for once?