The whole trusted thing is cool and everything, but the trusted members are few and far between. It was a great idea, but there's just too many hoops to jump to obtain it.
I'm not trying to change the system, but to add to the one we currently have.
I think something similar to eebay would be great. A different section where people can vouch or say how their trade went with that person with positive, neutral, or negative "bubble" clicks (not sure what you'd call them) and a comment section. You can also give colors for good and bad percentages so that people are wary of people with more than 20% negative trades without having to look inside their trader rating profile. Also code it in a way that multiple transaction but with the same person only counts once so you prevent inflating their rating.
Just a few ideas that would think benefit the trading community.