Coventry. Was just a bit grey and grim, though maybe it's changed since February 2003.
Luton. Grim, especially when my dad and I went to watch Burnley there in 1999 and IIRC kept getting turned away from pubs, because they hadn't realised the 80s were over and people can go to an English football match without smashing the place up. Infected me with long-held prejudices that the South East, especially the Home Counties, were the capital of soulless, humourless, unfriendly Tory anaemia.
Milton Keynes. Though perhaps only because I got stranded on the train there at 3 in the morning. Still, in a place of that size, there should be something going on rather than thinking I'd wandered onto an empty soap opera set.
Preston. Nothing against the place as a whole - the centre is okay, loads of good pubs and the university's come on really well in recent years. but as a student, I made a huge mistake living somewhere so close to home and so similar to where I was from, given there were a lot of bad, complex events in my teenage years and I needed to escape from that history by going to a much bigger and more distant city. And for the best part of seven years (though I wasn't studying there all that time) I wasted my life with Dutch courage "It's eventually going to happen, some day I'll fall in love with this place." I didn't. And every time I go back there I get existential dread.
Not sure where else but though there are plenty of rural Ribble Valley/Yorkshire Dales villages near Clitheroe which are wonderful to visit and like the dream vision of rural England for tourists and city-dwellers, I wouldn't like to live there. Farming families apart, there's nobody between the age of 18 and 50, everybody knows everybody else's business, and if you're not making money in a "conventional" job you don't feel that welcome. Plus they're often full of those Tesco Value sausage-faced bald men with ill-fitting glasses who go up to women on the bus and say "Cheer up, love, it might never happen," think Corbyn just wants to give students free stuff, and you're not even allowed to call it Christmas anymore. It's odd, in this identikit high street era, I'm a huge fan of local patriotism, character and expression - even Blackburn and Burnley, 10 miles apart, have different accents and seem to be in completely different eras - but a community like that demands you put so much time into the village you lose all sense of self.
You only have to watch the Love Thy Neighbour (no, not THAT one) documentary on Channel 4. I think this is true of a lot of "quaint" countryside all over Western Europe, though.