Haha, happy to help. X3 You're right, the narrative tendency is his one "villain foible" that really tends to put him on shaky ground -- the desire to explain how he did everything to his "victims". But instead of looking at it as gleeful gloating, you might want to look at it from a different angle. libekory were just talking about this.

We think that Aizen is kind of... educating them. After all, we know that Aizen's goal is hypothetically to do something good: he wants to ascend to the throne of Heaven because no one is there right now. People pray and scrape and bow to a god that doesn't hear them, isn't even there. He wants to take that throne because, theoretically, he wants someone to actually be there. He wants to lead, not destroy.

So with in mind that Aizen's ultimate goal is "benevolent godhood," this is kind of an educational moment. He is guiding these people in their mistakes, showing them where they went wrong. "This is why you had to die here. If you had done more of this all along, you would have been a better person and you wouldn't have been in this situation." Since we know that reincarnation is canon, even though he plans to kill them right here and now, the lesson could last into their next lifetime -- making them then the kind of person he would appreciate.

Just an idea.