Fionnuala- more Celtic mythology, but still my all-time favorite Celtic name for a girl.
Carys is also nice, and reads a little more mainstream (ie. pronounceable by most native English-speakers)... If it's a male you're looking to name, I'd suggest
Cionaodh or
Iarfhlaith, and I also like the look of
Iestyn...
I think
Eirlys is lovely.