[Alchemist007]

After reading that ^ post, I humored another thought of how Bleach could've gone.

Spoiler for Kinda OT:

Aizen did what he did in the SS arc just for the hell of it, for bloodthirst alone. He was tired of Shinigami this and Seireitei that. So he left for HM, he gathers 20 Vastos and leads the captains on about the King's Key. Then he attacks: Soul Society, starting with Seireitei. The Vastos decimate Seireitei in under an hour. Only a few captains and lieutenants manage to escape alive. Aizen becomes the ruler of SS and vows to make it a pure anarchy and introduces a permanently open passage for hollow to enter. Ichigo must then team up with the survivors and put an end to Aizen's plan. Wow, even that sounds like the Sensui arc from YYH.