Oh, so now Kubo has one bankai less to create, very clever. He had to do something now, since everyone expect all bankais revealed in this last arc.
First Ukitake fought off-screen, then he was one-shotted like a bitch, but now there was no escape.
And yes, I completely agree: Aizen's can breathe some life in this train wreck of arc.
Hell, brief mention of him resulted with no complaints about so many wasted pages in this chapter.