It's not a bad proposal, and I'll be open to at least trying something like this on a trial basis - or perhaps just designating certain featured threads as moderated.
Perhaps limiting a mods ability to moderate to a specific forum (US Politics, Canadian Politics, etc) or certain threads, which would allow them to participate elsewhere, while maintaining their little piece of the forum.
However, I am a strong proponent of freedom of speech, and I hate censorship - so even in a scenario above, severe restrictions should be imposed on the mods to ensure they don't remove unpopular opinions and or facts.