We're relocating in a year or two, and while good schooling for our clearly gifted 5yo is high on the list, family life ranks first.
I agree, I personally wouldn't base my home purely around my kids' educational needs although it would be a biggish factor. That said, we live in a city with a 1.5-million pop and I couldn't go any smaller than that - I love having decent museums, art galleries, public events, visiting speakers etc, for our own sakes as well as the kids'. I wouldn't uproot and move suburbs for a school zone. We've already had one kid through the school system and now know very well that it's a blip in the grand scheme of things. I'd rather stay in the house we love and spend on a private school instead.
As for the innate/enriched chicken and egg situation, I think the giftedness comes first. Yes our house is an very enriched environment but it wouldn't be unless we were all already pretty smart and interested, kids included. My kids get smarter than me around age 11, after that it's them hothousing me
