If you like Karlah you can speak about it, if you do not like it, you can also argue your position. It's simple
Karlah is compared not with evil heroes, but with good ones that are not yet in the game at all, there was not a single hint of them in the first act except Karlah which is not like the archetype of goodness what players usually would like to see
If you don't like Karlah, yeah, you can talk about it and you can avoid her in the game easily. But asking for her removal from the game is quite different thing.
I also like to play good aligned characters and prefer good aligned companions. So you saying that your idea of "archetype of goodness" is what most players would like to see is quite a stretch. I personally hate characters like Aerie and I think I would enjoy somebody like Karlah.
