I don't think there is a wrong way to play. I do different things and have a few game saves.
First I started a new generational family just a few days ago. My goal is 10 generations. I was half way there with my old game but the hubby had the computer hardware updated and I lost my game files. So I start with a couple and randomize their look. Start with a starter home and build it as the family grows.
In another game I play with pre-mades bcuz I really some of them and want to get to know them better and see where their story goes.
When new content is introduced I start a new game and try out the new stuff with one sim.
I have more but I don't stick to just one game one family. It can get boring when I play the same family for long periods of time. Which is probably why it takes me forever to do generational play bcuz I don't constantly play the same family. I play roationally and I play with various Sims of all shapes colors sizes and occult.