Two thoughts on HTTYD:
(1) They're moderate hits, at best, but people who like the films LOVE them. A smaller fanbase but possibly the same level of intensity as Potter.
(2) Vikings and dragons are two of those timeless archetypes where you don't really need to see the movie to know what's going on or be impressed. I think this is one of Dreamwork's strengths--Kung Fu Panda and Madagascar similar.
Thought on the Hub: could it be a mix of mini-lands? Scooby Land by Transylvania, Space Land by Potter ... maybe carousel is Trolls? In other words, a mix of IPs and original concepts. A Sanrio mini-land/shop could fit here easily. SpongeBob, too. Quite a number of minor IPs, actually.