Pretty simple, I went through all of the neighborhoods and bulldozed every lot and marked them all as residences. The entire world is ready and waiting to become anything you want it to be! Currently this includes:
Oasis Springs[TS4]
Willow Creek[TS4]
Newcrest[TS4]
Granite Falls[TS4:OR]
Magnolia Promenade[TS4:GtW]
Windenburg[TS4:GT]
San Myshuno[TS4:CL]
Forgotten Hollow[TS4:V]

If anyone besides me finds this useful I will update it with new towns as they become available. I should also point out I have no idea what would happen if you try to open this in a game that doesn't have the towns installed. Be warned, it could be bad.
Edit: I have gotten feedback that this still works if you don't have all of the towns!

For the sake of easy downloading there is one house with a family in it. It's my world, so I added my sister and myself! Feel free to delete them and the house if you want. They live in Windenburg.

If anyone downloads this, feel free to tell me in the comments what you do with it! Personally I am planning on keeping a copy of my "Empty world" on hand for whenever I feel like making a custom game. Apocalypse? Why not, no one is living there anyway! Recreating Harry Potter? Nothing is stopping you! Just going to fill it with the weirdest things you find on the gallery? That sounds fun!