where specifically would you recommend?
That depends on what you need. Along the west coast, up around Barmouth is absolutely gorgeous with mountains on one side and sea on the other, but it's not going to be as cheap as some other areas and you're far from any cities there. Go southeast from there into the interior and you get
verdant undulating hills and the most amazing small ribbons of black tarmac roads begging to be driven... even less densely populated, but it's incredibly affordable and you can get away from it all if that's your goal. If you need to be closer to amenities and potential employment, head south and try to stay within a reasonable distance of the M4, which span most of south Wales. Cardiff area is definitely growing as most jobs are advertized there, and the valleys north of Cardiff really are stunning, as someone said earlier. We settled northwest of Llanelli (near Swansea area), where we were able to afford a detached house with off-street parking, outbuildings and garden (not overlooked by neighbours!).* We're near enough to the M4 to be useful, but we can sit in our garden and only hear the sound of birds. We have a workshop for making things, a "barn" to park our car in, and a shed in the garden.
*Nobody tell him that our house needs a lot of work and we don't currently have a kitchen!