At the bold, no.. if Tsunade would've died (which she honestly should have), there should have been an entire chapter dedicated to her, she's the Hokage.
If you think I want her to die merely to open up a Hokage seat, then you obviously only read half of my post.
Her being alive has no relevance, the only thing she could do better as a Hokage would probably be paperwork... which Naruto could honestly have a right hand man for.
And to be honest, the seat of Hokage should've been stripped from her after Pain, because she obviously couldn't protect the village, and without Naruto, Konoha wouldn't exist.. but this really isn't about that, so lets no get into it.
Her having pure nostalgic moments with Hashirama shouldn't have voided her death, unless Kishimoto plans to kill her off in front of Hashirama, causing a frenzy.
And where exactly does this giant Chakra pool come from..? I know in the Pain arc she was attending to almost everyone in the village, but she wasn't making a large difference, leading me to believe that her healing wasn't sufficing.
Tsunade's death would have been very good writing, as it made much sense at that given time. I don't think Tsunade could get a better death than that, Kishimoto passed up a good oppurtunity.
Though, I'll restate this... It's Kishimoto's Manga, and he does as he pleases.