Conjuring dancing flames is fine, however, having multiple "forms" of a magic is a rather high-level skill. What would be more [i]plausible[/i] is if she chanted the spell and then fire the flames into the air, or somewhere they would fizzle out and exprie before they caused any damage. Magic cast by people without a falna is much weaker than that of those who [b]do[/b] have one, so it wouldn't be a particularly dangerous spell.

If you want some kind of illusion, that's fine too. It means you'd be screwed if you ever ended up in a situation where you're all alone in a combat-enviroment, what with being slow as heck and having no endurance or stamina, but hey, if that's your cup of tea, go for that instead. :)