Suleykah is really pretty, though I think I like the spelling Suleika.
Ceallach on the other hand I think would be really hard for people to pronounce and spell. I don't particularly like the sound (it's like KAL akh or K'YAL akh). I'm not sure where you live, but unless it's in
Ireland, this name is going to be really confusing to everyone who comes into contact with it!