Most of Stockton is alright to be fair, Norton is canny aswell. Just the area where benefit street was filmed that was grim and the centre really, don't mind it too much. Can't disagree too much about the centre of Sunderland really, the Bridges is the killer imo as it's just one shopping centre with not an awful lot more and it's not particularly very nice either. At least there's plans to try and change something, whether it actually happens though is another thing but to be honest it's probably better to compare Sunderland to other large town's imo. It's no different other than it got a title in the 90's, the centre has declined pretty much ever since it got it aswell.
Durham is the worst centre in the North East though, the place has so much potential with one of the nicest cathedrals in the country but it's just so poor. I always think when visiting pretty much any other old cathedral city how disappointed you'd be if you travelled all the way upto Durham. There's literally nothing to do.