It would be great to see some more Welsh railways. This direct service from Cardiff Central offers a substatial commuter and tourist route along the South of Cymru, from busy urban centres to quiet coasts. There are also lots of smaller branch lines that could be included, giving similar operations to the Cardiff Central DLC, alongside longer haul passenger services!
Agreed Route - Conwy Valley Line: Llandudno To Blaenau Ffestiniog | Dovetail Games Forums While your suggestion isn't bad by any means, you need a lot more explanation in it, like motive power, intermediate stations/yards, a map of the route, images of interesting locations, timetable mode layers, route length. Have a read of this Matt's Advice On Tsw Suggestions | Dovetail Games Forums
Cardiff to Fishguard also way too long for a TSW route. Even Swansea to Fishguard with maybe Milford Haven and Pembroke would be pushing it. Cardiff to Swansea probably more in the realms of reality.