Thanks for the suggestion - but it's not going to happen. I think it's a bad idea. I know this because I have done this sort of thing before and it's always a disaster.
Contrary to your assertions this kind of thing adds significantly to development costs (largely in the form of cleaning up the abuses of corrupt player moderators). By elevating players to special status you're creating an engine of corruption. It might not fail in the first day or the first week, but it's doomed to rot. The result leaves the community even more divided and bitter than before the system was implemented.
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