We lived in SF for 3 years while DH and I went to school there. We liked the city. A lot of great people there. VERY conservative though, so I tended to be out of the norm. I did get a few dirty looks breastfeeding in public, but I figure I'm just educating them lol.
Pretty much the entire city is run by the BIG hospitals. I delivered my DD at Sioux Valley (now called Sanford Health) with a CNM and had way more interventions than I would have liked, so if you ever want to give birth there I'd totally recommend looking into homebirth.
I can't help with schools as we had one newborn while there.
We lived in central sioux falls, right next to University of Sioux Falls and the cost of living there is really cheap, if you live just outside the city limits I think it's even lower. Now that we live in Minneapolis what I miss most is that low low cost of living!!
Good luck with your move.