i love the original Celtic spellings but fear that my children will forever be misunderstood where we live. (My cousins' father is from Ireland, and their names were not anglicized since half of their family lives overseas; also their names are very common in Ireland but rarely heard of in America.) So if i were to go with a name of Celtic origin i would most likely "anglicize" some of them.
i like:
Declan
Rhys
Bryn
Carys
Fionn/Fiona
Niamh
Lorcan
Seamus
and i've always loved my own name, Tara... since there are so many people out there who despise their given name i have felt very lucky.