I would like to share what I do for Naga's version of Sunset Valley.
I take and go through each world and pull out certain families, houses or special venues and save them to library.
For example from Latenight I pull out all the 2, 3, 4 and 5 star celebrities and most of the vampire families also.
For Moonlight Falls I pulled out some the fairy, werewolf, witches, ghosts and vampire families and again some the more interesting lots/houses.
All the other worlds I just pull out the houses I find interesting or like.
Once this is done I go through and place the homes in the Sunset Valley and make sure they fit and look proper and blend in and then move in the families carefully.
Then I start playing... and it really just gives you the best of everything the game has to offer in my humble opinion.
Thank you Naga!
PS: I also like to mention Union Cove, Setra and Jericho as other super nice worlds I like to play in.