Sample solution: We could expand the scale of the existing system. Add multiple discussion tiers; increase the karma requirement to post to Main, add a lower karma requirement to comment in Main, add a yet lower karma requirement to vote in Main. Do the same thing to Discussion, with lower limits. Add multiple tiers of discussion, where users have to graduate at each level to move up.
[Edited for tone]
Most of your suggestions have been made before, and are probably on some wish list. How do you get any of it done on zero budget is the issue. So the real question is how to get the necessary budget for the site development, not which features should be implemented.
Today's post, Well-Kept Gardens Die By Pacifism was originally published on 21 April 2009. A summary (taken from the LW wiki):
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