So, we've got the fight's resolution, which is nice. Kubo sure had us going there with Isshin mentioning his Bankai, didn't he? Oh well, guess that's gonna be saved for another day.
Anyhow, on to the actual events. So White is dead and gone, having blown up. When I saw the frame with his explosion, I thought he was utilizing High-Speed Regeneration for a second, which would've been interesting because that kind of power and endurance likely would've forced Isshin to at least try to use his Bankai. But the main thing I find interesting is that Masaki was able to kill it in one hit, albeit by aiming at its head. That kind of power level is not something that kind be glossed over later, and it'll be interesting to see how she uses it.
As for Isshin, we get the scene from Ch. 529 extended a bit and the aftermath of the whole ordeal. So Yamamoto was at least a little lenient back then, which is good. Mayuri wanted to study White's corpse (big surprise), which could have led to some...interesting discoveries. Oh well.
On to Aizen and the rest of Underdeveloped Antagonists Inc. Apparently, Aizen DIDN'T plan for this *audible gasp from around the fanbase*, which means this development is actually important. White was based off a Shinigami, yet focused on a Quincy instead. I'm not sure how Kubo plans to develop this, but it's very interesting, enough so that it inspired the chapter name.
And finally, Urahara's playing a part in this. Judging by his expression upon realizing Masaki could see him, I'm guessing he wasn't in a Gigai, so he knew she was spiritually aware. That look on his face pretty much confirms he's planning something; whatever it is will likely play a role in Masaki and Isshin meeting again. We'll just have to wait and see like always.
Anyhow, good chapter once again. Nice to see a break from the fighting and some exposition at long last. Now if you'll excuse me, I have to go finish the fight.