I’m female and I prefer playing with families. I usually start out with a single Sim, have him/her start a career, find a spouse, and have kids. I play with a lot of family oriented Sims. I try to limit the kids to 2-3 but, inevitably, they usually end up with 4, 5, or 6.
I really love toddlers in the game and think they are ridiculously cute so at least one of my Sims usually ends up with the fertility treatment reward. My favorite family at the moment is about to bring in generation 9.
Families to me are more interesting. Single Sims get boring fast and Sims in my games rarely stay that way for more than a few Sim weeks. I love looking at large, sprawling family trees, as well. It is really interesting to see how the kids’ lives turn out once they have been released into the wild, so to speak.
I'm female, and I usually start with a couple, they have a child (or two or three) and the child I like best moves out on their own when they become a Young Adult. They meet a spouse have kids, etc..., and the whole thing starts all over. I love to build though. It's my favorite part, so I set it up so that I get to build a new place every generation
This is how I like to play as well, have each new generation move out on their own and start anew. Once you get past a few generations, the family has so much money, I find it gets boring as there isn't as much of a challenge. And since I love to build, it gives me the opportunity since I tend to stick with one family for a long time.