I wouldn't focus too much on location yet. The 30-acre footprint is small enough that'll fit basically anywhere, the only impact location would conceivably have right now is limiting us through climate or regional property rights.
An indoor theme park (like at Warner Bro World) would be space-efficient, however, it would also be limiting and could transform the park from a miniature Disneyland to a glorified DisneyQuest 2.0 (not that there's anything wrong with DisneyQuest, but I don't think it quite lives up to the mantra of the castle parks). But it's certainly possible considering the success of parks in Dubai.
Regardless of whether we choose to make the parks indoors, outdoors, or a mix, it's important we emphasize the verticality of the park, Much like how Super Nintendo World has rides and paths on multiple layers -- Tomorrowland and Fantasyland especially could have multiple branching paths and stacked rides/restaurants to best maximize space.