Yeah, the original Sims was the best one building wise (making an amusement park in Making Magic as well as all the decorative items in Unleashed were lovely), I liked quite a few of the features that Sims 2 brought, such as the mobile phones, but all the fan-made stuff was what I truly liked (someone even made a number of horse carriages to buy instead of a car :D, and having a car to drive in most places without relying on a taxi or the car from work was very nice, not to mention all the landmarks you place around the town :3.
Sims 3... well, I didn't really like the way the sims or the objects in the game looked at all >.>... That and it takes up a lot of memory as well.