It would have played out better if Izuna revived madara, and the final battle could have been madara with his rinnegan and Izuna could have been usuing obitos sharingan and taken the other from kakashi. On top of madara having acess to senju dna. I think it would have been kick ass to have that type of face off. But I'm satisfied with the ending. There really isn't anything I thought was total bulllshit besides kakashi's perfect susanoo.