I feel that it's time we introduce a Loop line to TSW and there is no better place to start in that regard than London. If licensing and expenditure were of no issue, then the route that I see as having the best value in terms of potential gameplay would be: London Waterloo - Twickenham - Kingston Loop/Hounslow Loop It would be the easily the most demanding of London's suburban lines to replicate in terms of the AI traffic and required stock (playable or not) needed for authenticity, but it could also potentially have the highest gameplay benefits. These two lines are catered to by Class 455 and 707 services in the South Western Railway transitional livery, which I feel offers great variety in terms of age. They are also partially served by all other South Western Railway units (at least as far as Clapham Junction), with particular emphasis on the Class 450 and Class 458, each of which can sometimes be seen filling in for services on the Hounslow Loop in particular. The two Loop lines share a central section between London Waterloo and Twickenham which would itself offer a multitude of gameplay options and service patterns, from Reading/Windsor express services, to Rugby specials. From there, the lines seperate to serve Strawberry Hill and Whitton respectively. I have also personally encountered rare services which operate to Kingston's Bay Platform via Hounslow, with a reversing maneuver being required at Twickenham. Of course, it would be impossible to pitch such a line without discussing Clapham Junction, the busiest railway station in terms of traffic in the United Kingdom. Not only does this gargantuan station house 17 Platforms, it also has it's own depot/sidings for additional gameplay content. There is also potential for adding in AI controlled Class 377 units from the East Coastway release for additional realism on the Clapham Junction to London Victoria lines. Clapham Junction would not be the only location to house a depot or sidings however, as these can also be found at Strawberry Hill and Wimbledon in particular. Essentially, this route would be a "get what you give" type scenario, whereby the more you put into it, the more players could get out of it. There are so many options for adding to, or subtracting from what has been suggested here, be that focusing on just one of the lines instead of the two, or adding in branches to Hampton Court and Wimbledon (via East Putney) .