Actually i misspoke. I have not even replaced every lot, I have replaced community lots, filled empty lots. So a lot of base game residentials are still "intact" except for adding three lot traits to all lots. The idea, obviously, is for me to use this as my future base game, not just for this one.
Edit: I now also have a separate save where I am filling the empty lots, and mess around a bit. Most glaringly: I split Don and the Calientes up; he lives with mama Caliente, and their twin toddlers, while each sister also has a child with him but has moved out (one in Windenburg, one in San Mushyno (I can never spell that)) where they live alone with their daughters.
