Ultimately, and I'm coming at this from a completely different angle, visibility is important. Even if it's portraying stuff badly. Being queer myself, I've seen an increase of bisexual female characters in mainstream media and most of them were evil or slutty or troubled, or a combination of those. But amongst that horrible mess are The L-Word's Alice and Bones' Angela. Increased visibility will conform stereotypes, but it will also allow for better and more truthful characters to emerge. Or at least that's what I personally believe.