Ciaran is just way too trendy for me right now, even if it is a legitimate name. I'm just sick of hearing it and things incredibly similar to it right now.
Ciaran Diarmaid has way too much "eer" sound in it for me, but
Diarmaid is nice on its own.
Eithne Roisin?
Kilian Sean would be my pick, mainly because I can't stand the name
Patrick. I love
Kilian though :-)