From the perspective of plants she's a good guy since she tries to stop damage being inflicted on them.
From the perspective of people she's a bad guy since she quite often kills people and break things.
My work: http://www.fanfiction.net/~outside85
She's essentially neutral as she only cares about her plants.
I like her as a villain that has her own strong set of moral codes. She's an environmentalist. That has to always come first for her. She doesn't commit crimes for a whim. She needs to be a real character, with personal motivations. But the nature (lol) of what drives her clashes with what normal people would feel as right/wrong.