Ooh, great list! These are my favourites:
Iona BlytheIona EsmeIona FaelanIona Frances (can't use because family)
Iona JasmineIona JocelynIona Kinborough - I doubt my wife would let me get away with this but it's so cool!
Iona Kirsten (keer-sten) -
Kirsten is pronounced differently here but I really like the rhythm of this with the UK pronunciation
Iona LucyIona MairwenIona Margaret (can't use because family)
Iona RuthIona Sarai Iona SerenIona Sibyl - again, not sure that my wife would even consider this one!
Iona SylvieIona Tamsin
http://christineseaforthfinch.blogspot.com/