Definitely
Kira.
Kyra pro. KYE-ruh would be nice but I don't like it pro. KIR-uh, the 'y' just makes it confusing to me, it doesn't look like it should pro. the same as
Kira.
Heres how I'd rank the names plus a few I added:
KiraKeiraKylaKyra pro. KYE-ruh
Kyra pro. KIR-uh
Let me add I don't like spellings such as
Ciara because it could be confused with
Sierra.