I was born and brought up in West Yorkshire and came back to live here after over a decade in London.
In all honesty, I think the North provides more opportunities than the South East, but people often don't recognise this because they perceive "opportunities" in a rather specific cultural and economic way: usually career-related in terms of earnings and jobs, or culturally-related in terms of art galleries and theatres.
But what the North provides are opportunities of space, financial freedom and quality of life if you do your research and choose where you live carefully. It is possible in W.Yorks to buy a large house (four beds +) on a decent sized plot in a lovely area and get change from £300k, for example. It is possible for a couple with a child to earn a combined household income of £45k, and still be able to run a car and have a holiday every year. You can also live a "slower life" in the North because there's not so much pressure on earning a living just to cover the basics.
Personally, I wouldn't move to Hebden Bridge, even though generations of my DF's family are from there. It can be a bit insular, and I prefer a more mixed bag of folk (even though I am pretty crunchy myself). Plus the housing is more expensive, there's only one road in and out of the centre, and parking is a nightmare because so many of the properties are pre-war builds. It's worth looking at the Calder Valley as a whole and having a scout around to see what areas you really like.
"I've sometimes considered it but you have to consider why it's cheaper. If it was so great, wouldn't everyone move?"
To be fair, a lot of people have. There's a very noticeable reverse brain drain going on from the South East to the North now, as so many people under 45 are being priced out of London and the South East. Also a lot of people are looking for community, that sense of belonging to a place, having a local, neighbours that say hello ... that sort of thing ... and you can still find that in parts of the North.