Personally, I'm one of those in the small crowd of Disney fans who just doesn't "get" all the hype over Frozen; it's not a bad flick by any measure, but I think Disney has done better over the last several years.
That said, I can see how a Frozen overlay to parts of the Norway pavilion could work. Yes, the film takes place in Arendale, not Norway, but I think most folks get the idea it's Scandinavian in location, culture, etc.
The Norway Pavilion offers the best opportunity for a successful introduction of Disney's latest Princesses-du-jour into EPCOT. Would you rather see them at Mission Space, or perhaps the Land?
Look to the Three Cabelleros overlay in Mexico. I know, some might hate it, but I think it provided a fresh look to an old favorite that was getting a bit long in the tooth. And, even adding Nemo and Friends to old Sea Base Alpha seemed to work out; at least we got the clam-shell ride back!
As I said, I'm not a "Frozen-head," but I think the addition of another meet & greet and a well-handled overlay on the Maelstrom has the potential to make me want to visit the pavilion again.
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