She probably couldn't stand all the girls around Naveen.

Either Naveen or the Prince. Naveen is too obnoxious and narcissistic whereas the Prince is too awkward. I can see her going with Phillip. Phillip is enchanting, gentlemently and at the same time a flirty/playful type (he wouldn't hesitate to make a first step and actively flirt with a girl he likes as opposed to most of the princes that happened to get caught in a tricky trap of awkwardness and natural confusion when they were falling in love with their princesses) which were the traits that initially seemed to attract her in Charming. Cinderella needs a man who can be respectful and dominant at the same time.

Shang has trouble expressing his feelings to Mulan. A compliment like "you fight good" (can't think of a Cinderella equivalent) would not be the type of thing that would work for Cinderella. Cinderella needs a man to sweep her off her feet (why Charming was that man, I have no idea) and Shang can barely even get himself to pursue Mulan, much less sweep her off her feet.