For me, it kinda of depends on the story I'm making. While I do like City Living apartments because of the urban vibe, I think houses are more practical for getting sims out into the world, jogging, socializing, collecting stuff or exploring. I also love to build, and empty lots give me more freedom to make different shapes. I even like to create (fake) buildings in house lots and put lots of sims in different apartments.
With the latest patches, though, I've been seeing some cool neighbor interactions in City Living apartments, such as a neighbor inviting a Sim to work out. I also like making the transition in my stories: sims live and meet in the city, they're young and hard-working, and when they're older and get a family they move into a big house in the suburbs.