http://www.sciencedirect.com/science/article/pii/S1084804500...
Which was a bookmarking tool, that enabled you to create your own scoring system with multiple facets. Like the Slashdot: Insightful, Funny... You can't have too many of these as it can get unweildy (probably why Facebook settled for the Thumbs up), but it could help. Especially for a community that sees the outcome value and are prepared to learn and contribute towards community moderation.
Up and down votes are so ambiguous that I'd almost suggest they are practically pointless. The 'Mee too' and 'I don't agree' votes really need to be filtered out into something else. Perhaps into a 'Consensus' facet. Add to the mix 'Topicness' : 'On topic', 'Off topic'; 'Niceness': 'Pleasant', 'Rude' etc.
Word cap each comment too, so they remain to the point. Essays can be linked to.
For example-
"This is broken as it exists, for reasons A-E. However, if you did things X-Z, it would work much better and be much more interesting."
Sure, that takes more time. But honestly, if your main priority with your post is that you can write it quickly, you're probably not making a meaningful post anyway.
I wonder if an "are you sure" type button could help improve posts. Maybe it could say "Does this contribute to the conversation?", just to remind people what the point of posting really is.