I would be happy with story progression as long as---as many said above---there is an option to turn it off or on.
I was not always happy with the way it tampered with families that I had a clear plan for. Some sims I create are meant to be single, or live in a particular house...but sometimes the progression would change that. But, for other sims, it works pretty cool..randomly pairing up sims and having families come and go, just like in real life. And it was always interesting to see how the kids and teen would grow up.
I recall a time in Sims 3 when I got sidetracked by one particular family and was playing them for a long time. Then, while playing them, I noticed a ton of vampires walking around town. After checking, literally half of Sunset Valley had become vampires during story progression. If any of you have ever read Stephen King's "Salems Lot", it was just like that haha. I was going to go back to a previous save and start over, but then decided to change course and try to just play it out.
