2) The thing Yammi, Grimmjow, Ulquiorra, and Nnoitora had in common was that it was Ichigo attacking them. And just like 1), we have to realize that the Captains are not Ichigo. This is what I've come to accept. There really isn't any need to look further than that unless you want to burn some brain cells.
3) Agreed. But Aizen will probably punch a hole in Ichigo's chest, bringing for the incarnation that killed Ulquiorra. And the mask issue gets pushed to the wayside. Kubo should know he can't do that though for the sake of his 'completeness'.
4) I wanted Unohana to fight Yammi, but Agreed with you. She'll return and heal everyone. Will be interesting to see what she does about Hiyori though (cut in half). You got something against Hinamori? But she's so cute lol. Anyways, she was most likely to survive her injuries anyway.
5) Unohana bankai, huh? Sounds good to me. Although she needs to stop being a tease. She's capable of looking badass (the look she gave Mayuri about the Garganta), but she refuses to fight. Seems she's gonna be one of those 'It can't be helped/I've got no choice' characters and unleashes untold amounts of kickass when all hope is lost.