Wales a small place, but regional variations still huge. Vale of Glam very different to (say) Tregaron both culturally and climatically.
Weather in South/South-West Wales warmer and in particular drier than in North. Google rainfall maps of the UK. Culturally quite different also. Not all Welsh-speaking areas same. Teifi valley and North Pembs very Welsh, but not in-your-face about it. Mid/North by reputation a bit strident. Have never lived in North, can't say if justified or not, but have heard so many stories. Would guess depends a lot on attitude of incomers. If respectful of local culture, unlikely to be a problem.
Property near coast, especially in beautiful areas like most of Pembrokeshire, attracts premium. Compare (say) Newcastle Emlyn with St Dogmaels, both mentioned earlier. Both nice, both smarter and trendier than they were 30 years ago. Former is five minutes from beach, latter is 25 minutes inland = St Dogs more expensive. Further inland you go, cheaper it gets.
St Dogs & larger Cardigan - separated by 20-minute walk - kind of place you describe in OP. Good community, lots going on (pre-Covid anyway), choirs, cinema, shops, farmers market, etc. But still small, and 50-minute drive from Carmarthen and dual-carriageway to M4.
Narberth up and coming, chic-ish, probably due to good access to A40/M4. Don't know anybody who lives there. Towns of Haverfordwest, Milford, Pembroke Dock themselves gritty by reputation, but surrounding villages should be OK.
If living in village or larger, should be able get mains gas, but if outside a settlement then likely will need bulk (Calor) gas or oil. Rural areas may still have major problems with internet access. Get 2Mbit/s here, no sign it will improve. 4G might work.
In Welsh areas like Teifi valley, Preseli, Ceredigion, probably large chunks Carmarthenshire, children taught in Welsh in schools, and very seldom negotiable. Some people surprised by this, so good to keep in mind if you have/want children at some point. It is different country, after all. Obviously becoming aware of and learning new language (5-6) at early age has its positives.