I play legacy-ish style and only one household. It keeps my attention because I love my Sims and I find that it's hard to have in-depth backstories for entire worlds. If I rotated my gameplay would get same-y anyway and there's enough variety of personality in one household to keep me happy. My Sims are rich, but I find that creates opportunities for different types of gameplay instead of no gameplay. It's not hard to come up with creative ways to spend cash.
I find that playing slowly and deeply instead of widely helps my enjoyment. I keep my Sims very busy. They have lots of hobbies, jobs, friends, and relatives. They're always going out and doing things. It's not boring to me at all because my Sims always have stuff they're trying to accomplish.