Incentives for positive posting.
Those of us who are skilled (or perhaps just stubborn) enough to have played the Souls series are aware of a nifty little mechanic implemented in game. Players are able to leave messages that, when connected online via respective systems, appear on the ground for other players to read. For those who don't know, the Souls games are absolutely brutal. They punish those who rush into situations blindly and reward those who carefully proceed, ready for anything. In a lot of cases these messages can save a players life by warning them of an impending trap, or leaving hints as to the location of secret areas.
There is a voting system in place where if a message is either helpful, or simply witty and amusing, players can give it an upvote. The person who left the message is then rewarded with Humanity, an in game resource which allows a person to go from being basically a zombie to being human, thereby allowing them to summon other players or NPCs for fights. Having humanity also increased drop rates, and the damage of certain weapons or enchantments.
All in all, it's a good thing to have.
The Souls community is widely regarded as one of the best, even if not one of the more well known, because in most cases players are constantly trying to help each other. We all know how daunting it can be to tackle Lordran or Drangleic with nothing but the cold steel on our backs, and in a lot of cases diving into the League community can feel very similar. The system of leaving messages for other players, and the subsequent rewards for doing so, give strong incentives within the community that extend past the online forums and boards dedicated to helping nee and veteran players alike. It is a real time system that encourages players to help each other and incentivizes them stopping to take the time out of their day to leave help for another.
My suggestion is this: Implement a similar mechanic for the boards. When a summoned posts something positive, be it a board discussion or a comment on one, give them IP for it. One vote, one IP. Doing so would encourage people not only to use the boards more often, but also encourage people for being positive when doing so.
The difference between the Souls community, well respected by those who know of it, and of this community, generally regarded as not too welcoming in spite of the gems of humanity one finds amidst the many tunneled coal mines, is that Souls players want to help each other and have reason to do so in game. Most on League don't seem to share those same ideals. Perhaps the community would start livening up with this system in place, and people might feel better about posting in the boards as the chances of getting legitimate, helpful advice would slowly rise up over the fear of being ridiculed. The positive behaviors reinforced on the boards would more than likely transfer into gameplay, with people being more positive during matches as well.