I think [name_f]Io[/name_f] is usable [name_f][/name_f]- [name_f]Iona[/name_f] is familiar enough where I am, so people could get used to the eye-oh pn [name_f][/name_f]- and [name_m]Bo[/name_m] is being used so 
I like [name_f]Io[/name_f] [name_f]Lunaria[/name_f], [name_f]Io[/name_f] [name_f]Louise[/name_f] and [name_f]Io[/name_f] [name_f]Mavis[/name_f]! I’d be thinking [name_f]Io[/name_f] [name_f]Leandra[/name_f], [name_f]Io[/name_f] [name_f]Madelina[/name_f], [name_f]Io[/name_f] [name_f]Jemima[/name_f], [name_f]Io[/name_f] [name_f]Ginevra[/name_f].
[name_f][/name_f]I quite like [name_f]Io[/name_f] [name_f][/name_f]- it feels sparky and fun but magical too
[name_f][/name_f]I don’t find it too short [name_f][/name_f] [name_f][/name_f]- I like short names 
[name_f][/name_f] But I do like it as a nickname for [name_f]Iona[/name_f], [name_f]Ione[/name_f], [name_f]Iolanthe[/name_f], [name_f]Ionia[/name_f], [name_f]Ainoa[/name_f], and [name_f]Isola[/name_f]
Sibling names: [name_f]Io[/name_f] and… [name_f]Rue[/name_f], [name_m]Sol[/name_m], [name_m]Fen[/name_m], [name_m]Rune[/name_m], [name_f]Saga[/name_f], [name_f]Solstice[/name_f], [name_f]Clelia[/name_f]
[name_f][/name_f]Similar names (or rather, names that give me a similar feel): [name_m]Ru[/name_m], [name_f]Aya[/name_f], [name_f]Muse[/name_f], [name_f]Ceres[/name_f], [name_m]Eos[/name_m], [name_f]Ebba[/name_f], [name_f]Embla[/name_f], [name_f]Mabli[/name_f], [name_f]Naz[/name_f], [name_f]Sybil[/name_f], [name_f]Sybilla[/name_f], [name_f]Nim[/name_f], [name_f]Nimue[/name_f], [name_m]Iben[/name_m]
[name_f][/name_f]I think she could work [name_f][/name_f]- especially with [name_m]Mars[/name_m], [name_m]Ziggy[/name_m], [name_f]Paloma[/name_f], [name_f]Lua[/name_f], [name_f]Selkie[/name_f], and [name_f]Apolline[/name_f]