Thanks everyone - I hadn't realised that the 22/23/24 interworked or that the X21 had previously run through to Sunderland
The current 22/23/24 are both pleasingly simple (providing a fifteen minute service on each side of Peterlee, quite easy for passenger to understand, providing direct links) and very frustrating (given the awkward diversions to cover what were previously "Town Services" in Peterlee) and the massive dog-leg required to get from Durham to Sunderland on Arriva (rather than the GNE 20/X20)
There seem to be a number of places where routes are being chopped up to improve time keeping and also places where routes are added together to trim down the number of drivers/vehicles required and also tick a few boxes by being seen to provide a direct link (the GNE 42As from Wallsend to Kingston Park!)
RE: Arriva North East: Service Suggestions