I think she is a random and pointless character, if madara had turned out to be the true villain people would have been satisfied. Nobody asked for or needed a kaguya. I also don't like how kishi being afraid to elevate women comes out even in this god of a character. All the female characters in this manga are weak compared to their male teammates. Even tsunade who is probably the most powerful female in this manga does not stack up against any of the current kage or any of the hokage before her. In fact she is only stonger than mei, the only other female kage we know of. Kaguya has shown incapable of seeing through simple tricks and is being coached by black zetsu. Got to give kishi credit for that one. Who would have ever thought black zetsu would be the brains behind all evil in this manga.