Even if you don't care, lots and lots of other people will. That will be a huge hurdle that your daughter would probably not thank you for.
In and of itself I don't know if I like it or not. The O ending on a female name is interesting and uncommon and appeals to me. The downside of that is that with the S and ph plus the long O I can't shake
Sophie when I see it. I'm sick to death of
Sophie. :-/ So it is a definite strike against it.
I'm not a huge fan, either, of names that to me "belong" to one particular person.
Sappho is just
Sappho, not someone else's kid. Kind of like how
Che Guevara is
Che. The name is so "him" to me that it isn't up for grabs.
In real life, I would give it a thumbs down. As far as names go without context to me it's not bad but not particularly compelling.