Get rid of down votes
A lot of people will post something very enlightening or very topical others will enjoy, and so RIOT implemented an upvote system (similar to facebooks "like" system). When we upvote or like something, we've essentially given it our own blessing of sorts, as if we back up this idea. An upvote without a bump is described as "criminal" (jokingly, of course, but sort of seriously advocating a bump), and I feel RIOT has already addressed this issue and can improve it by making threads self bump with the "hot" feature.
Now then, on to downvotes. A downvote essentially is the opposite of an upvote, but it doesn't have the same effect because they do not require an explanation. If I upvote something, I agree, and I have formally backed up someone's opinion, and generally taken notice by RIOT or the community. A downvote disagree's, but it actually adds NOTHING to the forum discussion. In fact, it tends to kill threads and leave nothing more than a single page thread with tons of downvotes.
However, if you take away downvotes, people are forced to discuss and argue PROPERLY by actually giving written input. And then, if it is a compelling argument or something we can agree with, people will like that post as well. A forum discussion should not be judged by how many down votes something has, it should be judged by the actual conversation. Likes and upvotes add a sense of community and approval, downvotes (and I don't ever use this term lightly) are pretty much just toxic.