User blog comment:Salubri/Power Rating - Shinigami/@comment-44061-20151119033705

@Kman111 - Yes the idea is to do the other races as well.

@Kenpachi Thuggin - His ability to control his spiritual power has virtually nothing to do with his ability to advance, thats actually a issue of power lvl and skill. By this arc he has already perfected his bankai. Does he have room to grow yes. But the fact that he is prodigy and youngest captain speaks to his level of skill otherwise he would never been made captain. Part of that skill is the control only a captain can have. Thus Lvl of power is another matter. Also his endurance is where its at cause he has lost limbs and sustained internal injuries and survived them.

As for what zanpakuto support. It details a zanpkauto that is supportive in nature. Aizens zanpakuto is such a one it doesnt have any attack ability and no defensive ability it simply supports. He has to enact through other means.