Here is a suggestion for London Waterloo - Hampton Court & Guildford London Waterloo - Guildford and Hampton Court is a British route in West & Central London. To get from Guildford - London it takes about 30 - 40 minutes by train. The stops on this route are Guildford, Worplesdon, Woking, West Byfleet, Byfleet & New Haw, Weybridge, Walton-on-Thames, Hersham, Esher, Surbiton, Berrylands, New Malden, Raynes Park, Wimbledon, Earlsfield, Clapham Junction, Queenstown Road, Vauxhall and London Waterloo. The branch to Hampton Court also contains Thames Ditton & Hampton Court, coming of Surbiton. They could model Clapham Junction and surrounding areas based off of the upcoming Brighton Main Line. The locos on this route could be the South Western Railway Class 450 and the Class 444 in the new dark green-blue livery. Both of these trains can be modelled and slightly edited off of the BR Class 377 as it’s a similar design. This route could maybe have the EWS Class 66 for freight services down to Woking. Here are a few photos. (There are no photos for the Class 66 since it’s already modelled in the game) Class 450 Class 450 Cab Class 444 Class 444 Cab Map:
Whilst the electrostars and desiros are intended for a similar purpose, they are completely different and share nothing in common, so I don't think you could just model a Class 450 from the existing Class 377, if that is what you are implying. Otherwise a sensible suggestion. Might as well throw in the Hampton Court branch which is only an extra 2-3 miles from Surbiton.
This route would tie in so well with my North Downs Line suggestion with both routes meeting at Guildford.
That would be like including Tattenham Corner and Caterham branches onto the Brighton Main Line, probably too much for one route. The Hampton Court branch is more like the Reigate branch if you were to make rough comparisons, which is far simpler to do.
SWR currently use a dark blue/grey livery. This replaced the previous Stagecoach based red and white liveries.
A Surrey Rush Hour route meaning a GWE Class 166 on North Downs Line must be held at Guildford to let a London Waterloo Guildford Portsmouth service go then GWE Class 166 NDL North Downs Line DTG abbreviation proceed to Guildford. Why not get a Class 701 DLC
Ok then. That means Class 701 for SEHS CML but SWR still has them listed on their website as services to Guildford. IRJ after 4 free articles to which paywall starts has their service entry date as 6 August 2021.
The class 707 SWT had will be transferred to South Eastern on their metro routes out of Charing Cross and London Bridge. SWT still operates with class 701 trains.