What do you predict will happen with Xal'atath in the future?
She's not a fan of the old gods having been betrayed by them, she likes her freedom and plans - but we don't know exactly if she is evil.
Initially you assume she is because she is void and the way she taunts, but then she doesn't particularly play accordoing to alignements, her actions have been motivated by her gaining her freedom, and when she gets it, she doesn't turn into evil entitty ready to gobble up the player, and walks away from the old gods, very mysterious.
Do you thiink blizzard is going to further use her as an example to show not all beings of the void are evil? She does use a void elf appearance, and there is sitll some clarity fans would appreciate on how using the void might mean you being evil is not a fait accompli!