the number of posts that they could make would be very limited in comparison to other sections.
They only need one post,why give importance to the number ?
However, I think this is just useless cause 6 months from now there will be no account market and you will be able to buy a legendary for 0.05.This on an edge already.
In 6 months there will have the halving, so maybe the signature campaigns will lower their payout, so that's sure that the price will get lower.
Games & Rounds and Off-topic would be fine to exclude from the list. I see many trolls in Politics section as well and they aren't really discussing about anything related to bitcoins which again makes it Off-Topic.
I don't think this would stop spammers as I've seen people just posting without a signature and not even chasing activity points. They just love trolling while others anyways don't get paid for the above mentioned sections.
If you think like that, then why not just delete these boards, since they're not Bitcoin-related ? Except Games and rounds, where there is something to say, and even, I would personnaly keep it, the other sections all have something interesting.