Well, we live in the sticks and if we didn't have family and friends here and could afford it, I'd have moved to London like a shot. Even though I'm a country girl and would miss it, I think my girls have missed out on so many opportunities being all out here.
Things we could have got living in a nice big city -
Both DDs are into ballet. We have to go 20 miles to the nearest decent ballet school and now DD1 has even outgrown that. We are now looking at making the trip to London a few times a week. This is nearly 70 miles, so no mean feat. I see children who started their ballet in London and have had so many chances which my DDs have never had.
This isn't just ballet, of course, it's an example of a universal problem of living in the middle of nowhere. Friends of mine who do gym are in a similar position. I teach piano and one of my pupils who has done very well has just got a Saturday place at one of the London music schools. But she is limited somewhat by the awful journey and will now have to spend weekends travelling. DD2 was also offered the chance of a West End musical. We just couldn't do it; it would have cost us way more than she would have earnt and I would have had to give up my job to facilitate it.
So, from ballet to music to science to sport, whatever your kids get into in the future, they will have every opportunity at their disposal in London. You won't find yourself with a 2 hour train ride to get to do stuff. You can take them to museums, cinemas, theatres, musicals, plays, galleries, lovely restaurants, all without it being a huge day's expensive rigmarole.
Children in the country don't play out much nowadays. I used to as a child, yes, but those days have sadly gone. All you are left with is having to ferry your child everywhere, even to see their friends, because there is no public transport after 6pm and transport before is a bus stop half a mile away that comes once an hour.
Yes, the country is nice. Especially if you are retired and want soothing walks with the dogs (actually scrub that, we get run over by all the cyclists who have to bike because there is no public transport).
But for vibrancy, opportunity, fun, and a lovely cosmopolitan upbringing, I wish we'd had the opportunity of a happening city. My girls have so many unfulfilled dreams because they just weren't possible where we live.