From my memories of the 638 I remember having Verdes/Striders on it on a daily basis with the odd Dart here and there. Then when it got changed to the 773/774 it used Plaxton Prestiges which was quite nice at the time, before having MPD's when GNE changed it again to the 73/74, again with the odd mixture before it changed to what it is now the 2A/2C.
I don't whether the demand was there between Washington and Crawcrook back in the days of the 638 as I only used it as far as The Galleries, but since then I think maybe the Demand has grown in that area, and be worth re-installing the link again, obviously not the whole route, but perhaps from Washington to Winlaton would be suitable.
RE: Go North East Service Suggestions