Where next for Welsh narrow gauge?

For most of the late 19th and early 20th centuries, the main industry of north-west Wales was slate quarrying. The quarries fed a dense network of narrow-gauge railways, including the Ffestiniog and Penrhyn lines. Today most of the slate quarries are shut and the ones that remain send their product by lorry. The railways, however, are seeing a rebirth as tourist lines, carrying sightseers through the beautiful Welsh countryside. The first railway in Britain to be preserved by a volunteer group was the Talyllyn Railway. From small beginnings in the 1950s, the Talyllyn inspired a movement that has shaped the tourist industry in Wales and throughout the UK. But the Talyllyn started out with a railway that was already intact. One of the most ambitious preservation projects of recent times was the rebuilding of the entire Welsh Highland Railway from nothing more than an empty trackbed. The WHR had been closed and lifted in the 1940s. Nothing remained. Despite the legal disputes and controversy, the determined enthusiasts finally completed the rebuilt Welsh Highland Railway in 2011. The original WHR only ran from Porthmadog (where it connects with the Ffestiniog railway) as far as Dinas, but the reborn railway continues as far as Caernarfon on the former BR trackbed.
Using standard gauge trackbed as a basis for narrow gauge tourist lines has been tried elsewhere, notably by the Bala lake railway. An interesting case is the Llanberis lake railway, which occupies the trackbed of the former 4 foot gauge Padarn railway. The Padarn Railway originally carried slate as far as port Dinorwic, on the north Wales coast. Llanberis was also served by a standard gauge railway, which ran to Caernarfon. One wonders whether it would be possible to extend the Llanberis lake railway on this route to Caernarfon to meet up with the Welsh Highland Railway?
Another famous slate line I mentioned earlier was the Padarn railway. Here, again, a group of volunteers are rebuilding part of the line as a museum. The WHR demonstrates what is possible. It will be interesting to see how much of the Padarn railway can be rebuilt.

Talyllyn railway:http://www.talyllyn.co.uk/
Ffestiniog and Welsh Highland Railways: http://www.festrail.co.uk/
Bala lake railway: http://bala-lake-railway.co.uk/
Llanberis lake railway: http://www.lake-railway.co.uk/index.php/en/
Padarn Railway: http://penrhynquarries.webs.com/