User blog comment:Xilinoc/Ch. 589 - The Shooting Star Project: The Old and New Trust/@comment-24384892-20140716152243/@comment-5398287-20140716234625

Well, aside from big-name characters like captains and lieutenants, the Wandenreich has already ensured that the Gotei 13 will be devastated for a long time simply by having killed so many Shinigami. In all of the previous arcs combined not once did a Shinigami die at the hands of Aizen or any of his Arrancar; some came close, but ultimately there were no deaths on the side of the Gotei 13. In this arc, however, we've had 3000 people die, and as Mohrpheus explained in an earlier blog comment, that's far more damaging that simply killing a captain or lieutenant. This war is far from one-sided.

Honestly, I wouldn't mind if Kubo had some of the named characters die in battle, but only if 1. they at least damaged their opponent prior, and 2. their deaths weren't just there for the sake of "balance."