https://en.wikipedia.org/wiki/Newcastle_&_Carlisle_Railway Maybe a tad long at just under 60 miles and would involve modelling two complex locations at either end. However this route is often overlooked in favour of its neighbouring Settle & Carlisle line, but is actually quite a scenic and interesting run in its own right. In terms of era, classic 70's most of the traction already exists in game particularly the Class 101 DMU and Class 31, though 24's and 25's could also be seen on freight too. Coming into the 80's and 90's up to current day really, passenger services are/were a mix of Class 142, Class 143 (before they were sent to Cardiff) and Class 156. If done well it could equal if not better NTP.
Well the 101's were the de-facto unit for many years, at least until other types started arriving at Heaton. The 108's based at Carlisle primarily worked the Cumbrian Coast line or GSW locals.
Agree although I like the heritage stuff, bouncing along the Tyne Valley in a Pacer would be most appealing!
This is really the TVL from the sister game Train Sim 21. TVL is abbreviated form of Tyne Valley Line. If implemented the 2nd Trans Pennine Route after Northern Trans Pennine via Standege Tunnel.