Here's to hoping that Jo Rowling and her associates stumble upon this page.
Walt Disney channeled his characters' success by building Disneyland, where all the people who held Mickey, Minnie, Donald, and every Disney movie character close to their hearts could have a truly magical experience. I think J. K. Rowling should do the same. Build a wizarding world entirely based on the harry potter books.
Granted it will take lots of planning, hard work, and years to build and finish, the end result and its popularity may well succeed that of Disneyland today. Taking some cues from Disney, once again, I have formed a little
image in my mind that I would like to share. Now, to get to this magical wizarding community, you would have to take a train at King's Cross (this would of course be assuming it would be built in England), maybe a "9 and 3/4" special train or something like that. For added effect, it could be bright red, and a lady could push a trolley up and down selling pumpkin juice and all the hogwarts delicacies.
Hogwarts, of course, would be in the very heart of this wizarding community. It should serve as a hotel for all the guests who are staying overnight, complete with all of its decorations, portraits, halls, towers, and dungeons, and its ghosts. The main dining hall of hogwarts should serve as a restaurant, and should include the enchanted ceiling (I'm not so sure how this would be done though), with a buffet-style menu and waiters dressed as house elves. All of Hogwarts's proffessors should be roamin the halls, taking pictures with guests, signing autographs etc (maybe this is a bit too disney-ish, and should be left out).
Outside of Hogwarts, within walking distance, there will be a Hogsmeade and a Diagon Alley. All of the shops (Ollivanders, Honeydukes, Flourish & Blotts, Madam Malkins, The Post Office, etc.) and restaurants (Florean Fortescue's Ice Cream Parlor, The Hog's Head, The Three Broomsticks) should be created to match their book descriptions exactly, with The Leaky Cauldron at the entrance to Diagon Alley. The Leaky Cauldron could be another, slightly cheaper alternative to Hogwarts for overnight guests. Diagon Alley would of course include Knockturn Alley, a more darkened, separate place (18 and + only?). Now for attractions. There could be a Gringotts ride of sorts (visiting the vaults in a cart). The Shrieking Shack in hogsmeade can be a haunted ride (think disney's Haunted Mansion), and so can the Forbidden Forest...maybe it can turn into a night-time place for adults (think Disney Village, that opens after hours). Maybe play around with this idea, and have an Aragog Bar, with drinks, for adults of course. The Whomping Willow could be made into a roller-coaster, weaving from one branch into another going in a cart fast or something like that.
The lake can be an actual large body of water, where there can be boat rides going back and forth to hogwarts, and it can contain exotic fish and things. There can also be carriage rides around hogwarts and the rest of the places, driven by thestral-looking horses. Similar to Disney's Pirates of the Carribean, Peter Pan, and Snow White rides, something like this could be incorporated into the Dursley's Privet Drive house, a ride around and through the house dispaying all the mischief harry caused there (blowing up his aunt, escaping through the window by the flying car, dobby, etc), and can have realistic figurines moving around, popping up , etc (especially with dobby). The Quidditch field could hold real quidditch matches where the audience would watch from the stands (although I am not sure how they would get 14 flying witches/wizards on broomsticks in the air...maybe hologram projection?). Of course, there will be souvenir/gift shops abound, with all the books on sale and things like that...