I don't usually look for people who have lots of trading experience, but for people who can leave what I believe to be accurate ratings. I have done very little actual trading here in the grand scheme of things, and was put on DT initially by BadBear probably for my ratings on scammers which he must have thought were accurate enough. At the time of that I'd probably only engaged in one or two actual trades here other than earnings from signature campaigns etc.
This is kind of at the essence of the problem, the people the rating system effects the most, traders, are pushed to the side and lots of political games are played to the point it becomes less useful for those that need and use it the most. IMO there needs to be a requirement of some kind of material loss that can be documented to leave valid ratings. Either this or some other form of feedback that is purely for anything OTHER THAN trade.