For years my favorite Welsh girl's name was
Angharad. But lately
Myfanwy has been giving her a run for her money.
Glynis is a close third place. As for boys, I heard the name
Maldwyn the other day and I'm besotted.
From your lists, I love
Bronwen (kudos for using the female "-en" ending),
Llewellyn,
Nerys, and
Olwen.
Teagan is an English version of an Irish name, by the way. Mariwen is new to me -- is that a typo for
Mairwen? I like
Mairwen.