If this park is primarily fantasy themed in nature, centering it around Shrek's Far Far Away makes the most sense to me, especially if it's a hub and spoke layout.
I just can't see them having a partner IP in the center of the park, so no Mario or Bilbo there(or Kitty lol), and Berk should obviously be in the most northern part of the park, Po's Village in the east.
All of those are fantasy realms, so they'd fit around "the Hollywood of Fairy Land", plus the Shrek brand of referential humor would likely make it even easier to transition from Far Far Away to one of these other settings.
Would a big fairy tale castle hub-and-spoke be too on the nose though?