I would like to suggest a whole DLC covering the section of the Great Eastern Main Line between Ipswich and Norwich, as well as the lines from Ipswich to Cambridge and Peterborough.
ATS have some in fact most of this either released or as a work in progress. Their updated "GEMMA" line from Liverpool Street to Ipswich is out and the extension to Norwich is being made. Kings Cross to Kings Lynn and Cambridge to Peterborough are available and the link between Ipswich and Cambridge is also a work in progress.
Do you have any links that showcase these works in progress to check out? Are they still current because would very much like to see these completed and in game
It would require a very deep dive of the ATS Facebook website to find them! Some have been WIP for 4-5 years. The plan seems to be to make an Anglia West payware pack (which already includes the KX - Kings Lynn, Cambridge to Peterborough and the WIP Breckland line to Norwich) and an Anglia East pack (GEML to Norwich eventually, Ipswich to Cambridge plus any other GEML branches that can be added). Lastly they've made a modern Wherry Lines which will include the Sheringham line in time. So it's a bit all over the place with some WIP sections on hold and others currently being made, there's also a possibility that some of those working on sections have moved on, so release is delayed. I'm sure the ATS group would be more than happy to respond to any questions you have on their Facebook page. They are also making an AI only Class 720 but Alan told me on a stream a few years ago that he'd love to have a fully functioning version "one day". Perhaps they're waiting for a TSW version of the Essex Aventra so they can convert it to use on TSC like they are doing with the diesel Networkers.