I haven't had much to do with trust as I don't do any trading, but I'm starting to think that it should be associated with some of the breaches of the community merit rules. Exchanging merits, and buying and selling them is an intent to deceive the forum and its members, and I think it indicates a lack of moral fibre. This will probably influence the trading policy of the member in question.

I'm not sure that I understand how your proposal differs from the existing system.