It would be cool to have a Portsmouth To cardiff with A class 158 or/and 166 in GWR Since you already have the permission to use there liverys and things like that. Also the portsmouth direct line on TSW3 with the class 455,450,and 444 (and a few frieght services with the 66). Finally i know this is already on the to do list but it would be very cool to have multiplayer plus it would make alot of profit for Dovetail Yours Faithfully Harrison Playz
Multiplayer was abandoned a long time ago because dtg want to focus on the single player content and multiplayer brings on other more complex challenges. The PDL line would require dtg to have a swr license which they do not have at the moment. The 484 on island line 2022 was a fictional livery cuz they couldn't get the swr license, but they were in talks and they probably still are. So until the license becomes official, it will not come to tsw.