Do you really think Unohana would care what anyone else thinks? Not to mention it is what she herself desired above all else.
Besides, it's a point that not only was it something Unohana herself wanted (something which Isane understood, despite possibly being in love with Unohana), but it shows how desperate the Gotei 13 were. Willing to give up their best healer for just greater attack strength.
Yes, but it was Unohana's greatest desire, to right her biggest wrong, and it shows how close they were that Isane was one of the few people who understood that and accepted it despire her own feelings.
I honestly don't understand why you're making such a big deal out of this.
You can care how someone felt and still go against their wishes. She is her own person and is entitled to live her own life rather than limiting herself because of how Isane might feel about it. If she didnt care she wouldnt have left that letter
You know if Unohana wanted to make a better use of her sacrifice she could of just trained Ken till he was good enough then go and charge some invading Sternritters force to kill as many as she could before going out in a blaze of glory
It was both selfish and stupid, she could have waited until after the war to half her final showdown with Kenpachi instead of robbing soul society of one of its greatest assets. During a war for your world’s very survival is not the time for you to go out in a blaze of glory against your apprentice! She could’ve trained them up and then waited until after the crisis was over they have her final showdown, to die in a blaze of glory in keeping with the squad 11’s traditions.
You know, if the Anime does a 1000 Year Flashback when Yamamoto was Young with the other first 13 Captains, we can see the first Invasion the SternRitter of the Past did and see Unohana as the Kenpachi fight. That would redeem things because we all wanted that flashback, but never got it.
In her own words, she had to kill and revive him over and over again in order to bring out his full power and allow him to finally hear his Zanpakutō, which could only be done in a battle to the death. Hell, he didn't even INTEND to kill her and wanted to be able to fight her again, but she let him do it once he'd finally lost all his mental restraints because it was what she always wanted. So yeah, there's no "if she trained him well enough", this was the only way to prevent the war from being ended early by someone with the power to literally warp reality - even if she didn't know exactly that the enemy had such a combatant, she knew Kenpachi would be needed to take on the heaviest hitters, especially as a Special War Power.
You can not buy it all you want, it still happened, that's her canon motivation and explanation, it doesn't contradict anything about her previously established character and she's staying dead. In much the same way that, despite what I would PERSONALLY want for the story, Byakuya's still alive in a far more contrived situation.
I still find it contrived to have her die like that. There are other ways to get the same results without her dying. The same way I think that Yachiru being a Zanpakuto spirit while having a separate one of her own is contrived. Kubo really rushed things and screwed up things.