@Count:
But that is precisely why Oda won't kill off most of his characters, ironically enough. He wants his stories, no matter how dark and tragic they can get, to have happy endings. And to have a happy ending in Oda's eyes, there can't be any regrets. Having supporting characters sacrifice themselves when their deaths staying permanent are not necessary for the plot counts along the lines of "regrets" in Oda's eyes. He even clarified this on the record during one of his interviews.
@Eiichiro Oda:
"Basically I don't kill any characters because I wish the readers to feel satisfied after an arc ended." Asahi Evening Newspaper (26 November 1999)
I like to believe that people can change too. But at the same time, I think that expecting such change to be possible requires effort. Visible effort in words or actions to convince the people affected by past flaws/issues. It needs to be earned if the problem seems to be a habit that is tough to change. I personally don't give the benefit of the doubt to everybody that they can change. But I do so for the people who I see have merits and willpower to at least try doing so. If that makes sense..
I seem to be in the (vast) minority for this, but I enjoy the fact that (nearly) no one dies in One Piece, particularly for these reasons. There are countless other manga and pieces of literature where there is gratuitous death. One Piece is not one of them, and I'm glad for it. It's a purely uplifting story, about a crew that triumphs in impossible situations through sheer determination. There isn't a single arc that doesn't put a smile on my face after a reread. Not just satisfaction, but happiness. Of course, the real world doesn't work this way, but with all of the stresses of reality, it's nice to be able to read something that is purely entertaining, uplifting and even motivational, while still not insulting the reader's intelligence. The lack of death is handled masterfully by Oda IMHO. He still touches upon dark themes, true evil, suffering and hardship definitely exist in the series. Nothing comes easy for the protagonists nor the antagonists, and that's what makes it work so well. Everyone gets a chance to make amends and get up and fight another day, both the good guys and the bad guys alike.
P.S. Hi Nubtro.