The second of my route suggestions following on from the Stourbridge Shuttle. This one is to suggest my local train line, the former Great Eastern Main Line from London Liverpool Street to Shenfield, what has now become the Elizabeth Line between Shenfield and London Liverpool Street (High Level/London Paddington (Low Level)/Heathrow Terminal 5 (and 4 from time to time) I would like to see this route introduced alongside the Class 315 in either TfL Rail livery (see file 1) or the original Greater Anglia livery (see file 2), there is also the possibility of bringing in the routes former rolling stock, the Class 306 (in traditional BR Blue Livery(see file 3)) as DLC. I won't lie, i expect this suggestion to be taken far more seriously then the Stoubridge Shuttle due to this being an actual route rather than a shuttle; Hopefully this is taken into consideration and one day implemented as honestly it would be a privilege and honor to see my local train station (not saying which one) featured in-game.
Parts of the Great Eastern Mainline are frequently suggested. While it's a nice end-to-end idea, I would prefer a larger section of the line so that the fast lines could also be populated and usable to at least Colchester or Southend Victoria. No trains on the fast lines would make it very lifeless given that Chelmsford to Stratford is one of the busiest lines in the country.
It needs to be further than Shenfield. I know you are trying to be realistic but it only stops Stratford, Romford and Shenfield.
Great suggestion, as others have said, the GEML is frequently-requested and personally, I would have it go from Liverpool Street to Ipswich with the Class 90 and Class 360 included as standard with the Class 321 or potential Class 315/Class 345 (depends on era) as DLC