3. drill down on how only those merited posts were rewarded financially
Do by this you mean tipping? The money has to be coming from somewhere. If not from the campaigns then I doubt a typical user of this forum will feel the need to spend money on posts he finds entertaining. We're not on twitch.
For now ban all sigs and take time to develop a system that can cope with them in the background.
This would mean not only censorship (which most of us don't like) but also trying to regulate a decentralized economy that has managed to grow out of nothing. There was a demand for people to promote projects and there was a supply of people willing to participate. What's wrong with that?
Banning is the worst way. It's always better to reward people for following the rules, and for that reason I like the idea below.
For example the forum could track how many users in each campaign got banned or had their posts deleted by mods and adjust certain privileges based on that, e.g. limit the number of users they can hire. But that would basically require EVERY signature to be approved by the forum, which I guess goes against the "no screening" stance.
Publish statistics, make the managers responsible. They are the ones with the most to lose (high ranked, well trusted accounts, lots of merit, better deals than normal campaign members). If your participants are spamming and you get the highest number of:
members with negative trust
deleted posts
nuked spammers
(list up for discussion)
You lose the right to run a campaign, or get some other form of punishment, like some bench time for your account.
There are very well moderated campaigns out there, so the signatures by themselves are not responsible for the spam.
Banning signatures is comparable to banning guns because some people happen to be killing other people each year.