Stick with it would be my advice. You are unlikely to be able to buy the kind of place that you used to have in London with the difference in prices, your DS has settled at school and made good friends and it would disrupt all that again.
I think it's probably a case of rose tinted glasses, I moved areas some years ago now and had RTG for quite some time but there was no going back due to the prices of houses where I moved from.
We moved out of London about a year and a half ago, for the reasons parents usually move out of London - becoming worried about crime, wanting more space, fresh air, etc - and thought living in a small town by the sea would be a nicer environment for the kids to grow up in.
DS has settled well at school and made some good friends, but although I have become friendly with some of the mums, I haven't made any close friends. DD was born here and I thought joining baby groups would be a good way to meet people, but there aren't as many baby activities as there were in London (especially free ones) and again, although I've become friendly with some new mums, I haven't been able to make the step to close friends.
So, I miss my friends, the variety of things for the kids to do, and also the diversity and mix of people in London. But is this just to be expected in such a move? Have I given it enough time here? Am I just looking at London with rose tinted glasses because things haven't gone as smoothly here as hoped? (I'm even starting to say to myself crime is just something you have to live with in a big city)