How about give each user the ability to add a short message instead of / additional to the +1/-1 to the post?
-> It would reduce subsequent posts, because sometimes peoples only post because they want to tell with which part of the post they agree/disagree :)
Would turn this thread into something like:
POST
.line-break
.hr-html-element
.line-break
Responses:
@LittleBunnyWabbit> They like everyone else at -30 :P Now I have2get all -30 with troll accs!
Anarchid> Conspiracy incl.
Forever. You're on to something.
@-another-user> Don't like this idea.
Note: those post-comments can't be more than 1 (maybe 2) lines.
Would make responses not +1/-1 able, but they are limited to 1 for each user.
* So you don't need to give -1 when they don't fit into the thread because they are bound to posts, not the thread.
* Or give another +1, because they aren't for new ideas, but critism.
Finally I till you, why I have written all this above.
-> Because it makes it harder to give random -1 votes on may posts without letting others think, you in the Conspiracy Anarchid and fortaleza mentioned / let admins use the banhammer.