I have some ideas.
First, signature campaign managers are "supposed" to be the ones who ban people from campaigns.
Second, signature campaigns should pay people based on the quality of their posts (not on number of posts).
Third, payments shouldn't be made for signature campaigns if they adopt one of the following strategies:
  • Posts must be more than 75 characters.
  • Posts must be more than 3 sentences
They should add another one for pots being on topic with the OP.

Finally, users should NOT be paid based on rank, but on loyalty to the campaign.
Example: a user should have their payment increase by, say, 5% per payment.

Or, there could be fixed payment systems (that paymore than payment per post, that are more efficient)