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- Implement a reputation/thanks system (different than trust) with rewards for high ranking members
- Disallow eveyone under "Full Member" from joining a campaign.
- Automatically ban users with too much negative rep
- Ban campaigns that are poorly managed
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Have to much negative point doesn't necessarily mean that you are a spammer or post low quality posts, right ? A good example is : Quickseller. I agree with your other suggestions, waiting to see more...