This site is about posts, not people so we really shouldn't be encouraging targetting of individuals like that. That's only one small step from serial-voting, which is not allowed.
Hater is pretty insulting to people who are trying to keep poor quality posts off the site and if you're posting poor quality questions, either you should recognise that and improve or expect to be stopped by the system.
If you've posted 20 terrible questions, why shouldn't you be downvoted? What's hateful about quality control? Do you really think we want more bad posts to stick around or even more people to have to pointlessly read them because someone's worried about getting an badge named hater?
+1
great idea - I think you should get Exp for earning the LOVER badge, and lose Exp for getting the HATER badge.