So, I was thinking about it. Introducing Avatar as a "world" in Animal Kingdom isn't a bad idea, especially with two more films in the works with a significant step being taken towards sea life in the future films, but an Avatar world at Disney is not what is needed, especially when that Yesteryear article references a full human mythology world of griffins, unicorns, dragons, etc (which would possibly be better). Avatar could make a fun section of the mythology world like the Honey, I Shrunk the Kids play area that was at Hollywood Studios. Disney needs to go bigger than an "Avatar World" to compete with Wizarding World of Harry Potter. They need whole new park. And I got just the right idea.
"The Star Wars Universe." It's a guaranteed cultural icon, people will travel across the country just to experience it if executed correctly. Disney already has the theme park rights with the Star Tours ride. Some of the busiest times at Disney's Hollywood Studios are during Star Wars weekends where they have "jedi training" for the kids, Star Wars parades, and some B/C actors from the movies come sign autographs. Imagine a whole pan on that concept with different worlds of its own: Tatooine, Naboo, Kashyyk, and Bespin. And in the center of the park: Coruscant featuring the Jedi temple as the centerpiece ala Cinderella's Castle/Spaceship Earth/Tree of Life. Set the theme around 1 year before Episode 4, have Vader welcome you to "his Galactic Empire" and have signs with C-3PO and R2-D2 guide you around the park giving you "helpful" hints/directions or signs saying it's a galactic crime to litter in the park with Vader standing on it looking menacing. It'd be the greatest thing ever and would make bank with the amount of merchandise sold at all the gift shops (and the tie in foods, everyone would get blue milk much like how at Harry Potter everyone gets Butter Beer).
So, yeah, Avatar is not a bad idea, it's good one. But it's not a GREAT idea. If Disney wanted to be ambitious, go for the gold bar.
Oh right, zoos . . . umm, the Naboo area could have an aquarium and the Kashyyk world could have a lot of plant information. Maybe there could be a pseudo Dagobah world and fill it with snakes and lizards . . .