I had a bunch of ideas about how to implement this differently from everyone else, but for every idea I had, I was eventually able to think up some annoying side effect I'd rather not deal with, so I'm probably just going to make it work the tried-and-true way everyone in the world is already used to.
Thank you for your attention to this matter.
One of my ideas was to tie votes to comments so you'd have to leave a comment in order to vote (essentially forcing you to explain your vote or classify the sentiment of your comment as positive, negative, or neutral). But then I'd have to ensure you could only comment once at every level of the tree so each parent would only receive one vote per user.
i had an idea for a site i called censorboard, which was basically reddit, but you could follow 'censors', who could basically just mute/block/whatever people and posts, and you would inherit their actions. maybe something similar could be cool, where if you add people to an updoot whitelist, their doots are worth more than normal doots, and if you add them to downdoots list, then their doots are worth less.