We're English although have Welsh family on both sides, my mum's relatives are all Welsh, my husband spent a lot of time in Wales growing up, so we have been influenced by Wales for our daughters and now we're trying to come up with a name for our first son.
We currently have Isobel (not Welsh, I know) Siân and Carys. They're names that aren't too obscure here nor difficult for the English to say (once you get past "Is it Sigh-anne or See-anne?" 
).
Things we're looking for in a boys name, not so Welsh that we start to look themed, not David variations, I'm personally not keen on John variations because of having a Siân although he seems to be going that way. I don't mind if it's Scottish/ Irish names either actually, Isobel is the Scottish spelling, or old English names - the girls and I suggested Warwick as we got married there and I take the girls a lot, but he's not keen, although my mum (the only person we really trust with names during pregnancy) is, so feel free to tell me it's a good name 