When it comes to how difficult D&D
should be, I find that killing off PCs left and right is counter productive for me. The threat of death? Sure. But stacking up body counts? Death just ends a PC's story.
If a player is tired of running a PC, they can always just let me know if they want that PC to exit stage left at some point. I'll figure out a graceful way to have them disappear that makes sense to the story.
Of course different people play for different reasons and if your game looks like
and ya'll enjoy it, more power to you.