I honestly just don’t see how it’ll be done well
The beheading thing is excessive. Too dark for one piece to be done by a protagonist.
Ceremonial Suicide or death penalty would show that throughout all this in the past twenty years, the people of Wano have not learned a thing from the mishandling of the Kurozumis which is bad too.
It wouldn’t ruin the arc but it wouldn’t save it either. I don’t hate Wano, I do dislike a lot of what’s been going on, but it can be worse.