Rolling stock: Class 180. The class 180 Uses a Air brake system and a AWS Safety system while using a Scharfenberg coupler. This train has a max speed of 125 mph The grand central line connects London with Yorkshire and the north east with two routes: North Eastern and West Riding. If this route where to get into the game I believe both North Eastern and West Riding would be in the game (the total of stations with both of them is only 15) with a total of 9 tph on both routes. The North Eastern line which has 5 tph with 7 stations which are: London's king Cross, York, Thirsk, Northallerton, Eaglescliffe, Hartlepool and Sunderland. On this line In Hartlepool and Sunderland you would see northern services on the Durham Coast Line. The West Riding Line has 4 tph (3tph going via Pontefract Monkhill.) This route serves 9 stations Which are: Kings cross, Doncaster, Pontefract Monkhill, Wakefeild Kirkgate, Mirfield, Brighouse, Halifax, Low Moor and Bradford Interchange. Overall this route would be amazing to play in TSW2 as it adds kings cross (one of London's busiest stops) and adds some modern trains up north which fills a few gaps which the UK in tsw2 has. Now the distance could be a issue with it having 171 miles however I don't think that would be a issue (With it having so few stops.) Thank you for reading, Poisoned/Lucasfor/Whatever I'm called on this website.
Sadly it wouldn't be practical. The scenery for a route from London King's Cross to Bradford/Sunderland would likely be over 400 miles, and you would still need to model and program all the stations and services that Grand Central do not operate. They're also a bit of an awkward train operator to integrate since most stations they run between are of awkward lengths and/or routing.