I prefer
Sophia /
Sophie.
I grew up in a country where
Sofia /
Sofie are the spellings to use, and to that extent, they'd ended up looking a bit boring to me. The 'ph' in the others just makes them look more, well, sophisticated (and wholesome) to me.
"This is, EXCUSE ME, a damn fine cup of coffee."- Special Agent, Dale Cooper (in Twin Peaks)