I'd love to see Wales get some love like England and Scotland, it has lots of different routes and I reckon a 2000-2010 era Valley Lines DLC out of Cardiff Central would be fun to run as I've travelled the lines a dozen times and it's a nice region to travel through. Otherwise a Heart of Wales or North Wales Coastline from Chester - Anglesey would also be nice to see!
If you want to see some Welsh routes you have to give specific examples. Make your case on why it should be in-game, give details like route length, trains, services, etc. Use one of my suggestions as an example of how to do one https://forums.dovetailgames.com/threads/wcml-birmingham-manchester-via-crewe.72904/
If your looking at some suggestions specifically in Wales (Cymru) I have made some goods one you could use as a sort of template. The links are below, just pick a line and era and you'll be off. Train Sim World 4 - South Wales (cymru) Mainline (swansea To Bristol) Late 1980s | Dovetail Games Forums Train Sim World 4 - North Wales (cymru) Coast Line Mid 1980s | Dovetail Games Forums
