I don't care for
Layla, esp. not that spelling because of the LAY in it. And it just makes me think of the old
Eric Clapton song (even though that's not a bad association).
Leyla looks like it would be pronounced like
Layla, but I don't care for the spelling. Could be confusing imo. What about
Laila? (is this usually prn. like LAY-lah? I'm not sure...)
As for
Leila, I prn. it like LEE-lah. Of the 3, I prefer this one.