Aside from wrapping ordered and unordered lists in a class and then setting max-width: X characters and margin: auto, is there any other (easier) way to set a character limit per line in the body of a post?
This would be implemented a theme, so you could research what’s possible with CSS.
According to this, you might have some luck with specifying a value in
ch (character) or
em (em-dash) units: