I have different saves. Each save is a separate "story". In some of these saves/stories there's only a single Sim or single family I play, and if there are others Sims I created, they're just to be interacted with by the main cast, but I never take direct control of them after I have created and 'fixed' them (skills, career, etc).
In other saves, the story is more complex and involves different families that I play rotationally. In one such stories I have a large community of spellcasters with an intricate family tree due to intermarriage between the different families across generations. Eventually I succeeded in having two children who can boast direct descent from all the ancient founding families.
I've also just started a new save with different families in HoB. These families all all somewhat connected because they are relatives, inlaws or friends. They all live in HoB and occupy all the residential lots (I evicted all the pre-made Sims). The idea was to create a close-knitted village community. There isn't a single main character or main family, but I play all of them equally.
