From the ground up. Funds are unlimited, and any location in the world is available.
Where should it be? What features, attractions, entertainment, rides, exhibits, restaurants, accommodations, etc.? Family area, adults only area, teen section, child care, pet sitting. It has to appeal to a broad range of types: geeks, cooks, pet lovers, intensely political/argumentative types, introverts, party animals, sports lovers, couch potatoes, danger lovers, fraidy cats, career-minded people, as well as slackers.
But it must have features that uniquely mark it as a Straight Dope Enterprise.
Go forth and design!