1. Mizora and Minthara aren't confirmed as companions and they probably will not be. So I don't understand why would you compare Karlah to them.
2. You don't even know anything about Karlah. If she says "fuck" sometimes, doesn't mean that she is not good aligned.
3. "I personally don't like Karlah therefore I think everyone doesn't like her and she should be removed from the game" - is not an argument.
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