One thing you've not mentioned: the Tyne and Wear Metro shares tracks in the northernmost section, from Newcastle to Sunderland. Would love to see the Metrocar in game, assuming we get a 156 from somewhere else. We'd also certainly need the 801 converted properly to an 800. Otherwise, would be ecstatic to see this in game.
I went on this line a few years ago, I am sure it went as far as Nunthorpe beyond Middlesbrough where it terminates?
LNER axing the link to Sunderland, as of the Dec timetable I believe. Hope that if this route comes, it comes in the 'current era' where they operated on this route - albeit with very few paths.
LNER only operate one service each way per day between Sunderland and Newcastle, albeit they do use it for diversions. Most if not all services continue beyond the extents of the Durham Coast Line to Nunthorpe to teh south and Hexham/Carlisle to the north.
For me, for all the service is busier and more varied now, i'd rather it set when the pacers were around. We had a fairly unique spec for pacers (and 156s tbf) with high-backed seats, which were surprisingly comfy.
It's actually a link to a thread I made a few years ago now, proposing this route set in the mid-2000s.
