Another option would be heading-based voting, i.e. if you use headings in your comments, each one of those could become votable, or be treated internally as separate comments to vote on and reply to.
However, one problem with all such approaches (besides the big issue of increased UI complexity, of course) is that they’re kind of incompatible with the ability to edit one’s own comments—what if someone votes on a block quote or heading in you comment, and then you edit that part, or remove it altogether?
Another option would be heading-based voting, i.e. if you use headings in your comments, each one of those could become votable, or be treated internally as separate comments to vote on and reply to.
However, one problem with all such approaches (besides the big issue of increased UI complexity, of course) is that they’re kind of incompatible with the ability to edit one’s own comments—what if someone votes on a block quote or heading in you comment, and then you edit that part, or remove it altogether?