Part of the magic and the success of the books and movies is that it is all English! The author, locations, actors, everything is so English! It will lose a lot of the magic for me having it in Florida. I would go to England just to go to this park alone if it were there, but I won't go to Florida just to enter "Hogwarts".
1-Scotland...pretty much anywhere in Scotland would be magical!
2-York or the Yorkshire area...just because it is my favorite place in all of England!
3-Pretty much anywhere in Great Britain would be better than putting it in Florida.
The question you may be asking is will I go to the park next time I am in Florida? HECK YEA!!! I will just be comparing it to what it could have been if it had been located somewhere in Great Britain!
Maybe if it is successful enough they may open another one in the UK in the future. HOPEFULLY!
Here is a link to the Official web-site about the park, Check it out: