I don't like the "like" or "dislike" system. I used it on my forum for a short while, and it greatly hurt content as people would just like or dislike posts rather than adding useful information or contradicting information.
What I would like to see is a reputation system. That way people could give + rep to those who post useful information. It would be a way to identify the more knowledgeable members.
Another thing that could work for that is to create a badge system. It would allow for a badge to appear next to or under a person's username. The badge would be awarded only to those who display exceptional knowledge and contribution to the forum. Only an admin would be able to award the badge, with nominations and recommendations from forum members, verified by their posts, and be granted with formal recognition.
My main concern with the forum is the maintenance of useful, factual information and retention of those who provide it. Knowledge and experience should be recognized, valued, and respected.