My house!
Quality or quantity, it doesn't matter.
It's a 45 minute drive to Coney Island or Rye Playland; an hour to Great Adventure, Dorney Park or Quassy; 75 minutes to Lake Compounce; 90 minutes to SFNE, Knoebels, Hersheypark or Morey's Piers; 3 hours to SFAmerica or Great Escape; 4 hours to Kings Dominion; Canobie Lake, Darien Lake, Seabreeze or Lakemont Park; 5 hours to Busch Gardens Williamsburg, Kennywood, Martin's Fantasy Island, Funtown Splashtown USA; 6 hours to Canada's Wonderland, La Ronde, Waldameer or Marineland Theme Park & 7 hours to Cedar Point or Kings Island.
I don't need to mention all the smaller parks along the Jersey shore or in Pennsylvania that are 30-60 minutes away, do I?
I also live 20 minutes from Newark Airport, so getting to Florida, Texas, Cali or even Europe for that matter, is a breeze.
So yeah, the best place for theme park enthusiasts to live is somewhere near where I live in the western suburbs of New York City.