Maybe it's okay to enjoy not sticking with the same save/Sims. Do what you enjoy!
For me, I enjoy making all of the households relate to each other in some way. Friendships, marriages, coworkers, et cetera, are all meaningful to me. I love it when the world feels interconnected.
For some reason, the Strangerville pack was what ended up making just another household become my main household. It was a really fun back story for me: A sweet guy from a place equivalent to the midwest ends up being forced by an agency equivalent to the CIA or something to have a female secret agent live with him so she can investigate the Strangerville mystery. There was something about having them work on the mystery together that made me fall in love with this household. And I enjoyed having to make changes to his simple little house to accommodate the new member. Then I ended up creating his extended family: parents, grandparents, cousins, and second cousins. The game's little surprises helped me bond with this family too: When he thought he'd have one child, he had triplets, and then he got abducted and had twins. Then I had his father move in with them, which was interesting too.
I hope something I've written helps you.