I like
Rowena, almost enough to use.
Rowenna sounds highly unattractive to my ears and looks like a spelling error.
Ravenna ... I dislike place names for people, and though I don't know about the movie, if you say it's abhorrent I'll believe you! I suppose they picked the name as an elaboration of
Raven, which is the ultimate bird of ill omen and not a happy choice either, I would have thought.