Perhaps the allowed signature styling should change with activity score / membergroup. Like:
- Newbie: No styling (including links) allowed. Max 40 characters.
- Jr. Member: Links allowed. Max 100 characters.
- Member: Unlimited length.
- Full: Color allowed.
- Sr. Member: Size allowed
- Hero: Background color allowed
Then newbies will be less effective advertisers, which would hopefully significantly reduce the incentive for low-content posts. And when people become capable of effectively advertising through their signatures, they'll have invested a lot of time into their accounts, and they won't risk being banned by spamming.
Can this be stickied somewhere please?
I think that's a fair change, the vast majority of the spam is definitely from Jr member/member accounts. I restricted my promotion to 50+ activity for the last two rounds but it doesn't take very long to get 50. I did make some attempt to disqualify spammers but it was pretty much near impossible to thoroughly look into individual users. What would kill spam completely is probably basing the payments off activity which I'll look into doing if I continue this promotion. If you'd like me to stop doing this entirely I'd be totally willing to cancel it, there are already many competitors though.
Basing it off activity wont really work for you or users. The advertisers who have offered deals based on activity before have quickly been exploited and shut up shop. The Ritz Grand Casino deal did this by paying people upfront and more for the higher activity you had. People signed up and made little to no posts and some users were buying (or trying to buy) higher activity accounts just to claim the payment (one guy was actually banned for hassling users via PM to buy their accounts). If you paid per activity earned that month all people need to do is post twice in each two week period then they've got their full 28 activity for that month.
As I've said numerous times before, a simple solution would be to just crack down on spammers and treat them how you would any other spammers with or without a signature deal. The community can police the deals themselves. Just report spammers and abusers to either the mods or sig providers and they'll be dealt with appropriately.