Jon, I think consistent control and discipline might be too much to ask for in such an open forum, but perhaps such controls might be useful for some. I think using brain and eyeballs should prove sufficient for most users to scan for prominent threads, but the prefixes could make the process simpler. A "not" selector would be quite feasible. I'll analyze your suggestions and those of the other volunteers and members and try to formulate a solution.

Thanks,
Jeff