I think Ceilidh is Scots Gaelic?
In Irish we say Céili - Kay-lee. It seems odd to use it as a name though. Like calling someone "disco". It does have a nice meaning though. Céilis are usually pretty crazy, physical, sweaty affairs though and I can't escape that image.
I don't know where you live so I can't say if they are usable. I think
Aislin is more user friendly for non-Irish speakers than
Caoimhe.
They are a bit boring to me since they are pretty popular here.