Sole has a pretty sound, but I think that in English speaking countries it would be a problem unless there was an accent on the "e." A "sole" is the bottom part of a shoe. But the meaning is cute and I see it more of a feminine name.
Compared with others:
Sol-
Will always be a short form of
Solomon to me and I don't immediately associate it with the sun.
Soleil- I think this is the most intuitive for English speakers and it is pronounced the same as your Sole. The word itself is French but many English speakers know how it is pronounced due to Cirque du
Soleil.
Sunniva- Pretty, but not my style.
Sorin- I like this name a lot, but I am reminded too much of the word "soaring."
Helios- Nice sound, still not my style.
Names meaning sun that I prefer:
AeliusElanorEloiseHinaMarisolRaviSolveig