Hi amyrose!
Take it from another recent lurker and also a fellow "commitment issues" simmer, there is nothing wrong with starting fifty billion save files and never going anywhere with one of them!
No, but seriously, I've learned to love my sims' children and grandchildren and so on. The trick is to find a way to make them different. When you're getting bored and say to yourself, "I wish I would have made my sim X," then make your sim's child X and keep on truckin'. It's worth it just to see the neighborhood grow and change so you aren't stuck with the same friends over and over and over again (keep Story Progression on! Simmers who don't are stuck in Sims 2 Land, I think - come to the future!!!!).
Actually, I think that is the main motivating force for me to stick with a family past generation one. Just to see what new sims the game will throw at me, because, quite frankly, I'll be happy if I never see Christopher Steel or Jamie Jolina again.
goat
