I love [name]Laila[/name] because I love the book A Thousand Splendid Suns but [name]Layla[/name] is the more obvious spelling. As for [name]Lila[/name]/[name]Lyla[/name] I prefer [name]Lila[/name].
I actually think that [name]Leila[/name] looks most attractive, however, I voted for [name]Layla[/name] because it makes the pronunciation absolutely clear. I have known 2 people named [name]Leila[/name]–one pronounced it “[name]Leela[/name],” and the other pronounced it “[name]Lilla[/name]” (like [name]Lily[/name], but with an “a” on the end). If you don’t mind having to correct pronunciations occasionally, or if you live in an area where you feel certain [name]Leila[/name] will automatically be said as [name]Layla[/name], then that is the spelling I actually prefer!
[name]Layla[/name] and [name]Lila[/name] 
I like [name]Layla[/name] the best.
I don’t normally go for Y names (even though I have one - maybe that’s why!), but I voted for [name]Layla[/name]. The pronunciation of the other spellings just isn’t very clear. Also, I think I even like [name]Lyla[/name] with a Y better than [name]Lila[/name]. [name]Lyla[/name] looks like the feminine for of [name]Lyle[/name]. [name]Lila[/name] looks like it could be pronounced Lie-luh or [name]Lil[/name]-uh (like the beginning of the word lily). I just think the Y spellings make the pronunciation clearer.
I don’t care for any variation of [name]Layla[/name]. I also would hate dealing with all the spelling variations. As far as [name]Lila[/name] vs [name]Lyla[/name] goes, I definitely prefer [name]Lila[/name].
I prefer [name]Leila[/name] and [name]Lila[/name].