1) Allow forum moderators to penalize users by revoking signature display rights for a month for poor posting habits.
A little bit similar with this one for signature campaign, but its ban.
Campaign Participants:
Staff do not want to hand out bans for unconstructive posts but if we feel that you as a user are continually making very poor or unsubstantial posts due to your paid signature the following bans will be issued:
First offence: 7 days
Second offence: 14 days
Third offence: 30 days
Fourth: Permanent ban
2) Penalize bounty campaigns and ICO's that use bumping by shit-posting by displaying their thread permanently on page 10 or a special penalty page which reduces the size of their images and fonts.
How about locking their thread for someday (ex. first warn is 3 days)? But moderators will have extra works for this one.
3) Provide preferential listing on page 1 for ICO's and Bounty campaigns that pay to be listed there. Rather than paying an army of shills they could be paying bitcointalk to be listed on the first (featured) page.
Looks good, but how about scam ICO that pay for to be on featured page? It will bring a negative side for bitcointalk, except it need some extra research for it.