If you were to change the W5/W6 the why not keep them the same along their current routes but extend the W5 from Concord to Sunderland along the 56's route. You could terminate one 56 from Newcastle at Concord every 30mins if it were to improve reliability on that route.
Also, why not extend the W6 from Barmston Court to Waterview Park then Sunderland via the 73s route (not the round trip to Concord) creating much better links to Sunderland and getting rid of the mess that is the 73.
RE: Go North East Service Suggestions