Simple [possible] solution: restrict the number of downvotes and force people to prioritize.  Further, you should get future downvotes only as a function of how many downvotes you already have.  If you have 0 downvotes, you don't get to do it again, ever.<p>In this way, downvoting stops being a privilege you get at karma X and starts being something that's not to be squandered.  I believe (or maybe hope) that every person here internally wants hacker news to be a good community, and that change will make them cognizant of the fact that downvotes are for special occasions where discourse is uncivil and not for "puttin' noobs in their places"