- Only allow one post in a thread to count toward post-counts per 24 hours, and perhaps hide/limit signatures in the excess posts as well, addressing purpose #3.
I think that the first three would be fairly easy to implement, but the last is more difficult. Also, it'd be nice to get rid of the 64k limit, but that's also difficult to implement.
This one is unfair for good posters because good posts are always good posts. If one knowledgeable user answered to help the others (one or maybe more users) in one topic with more than one post per day, and their posts help the others clear their questions and help them solve their problems, it will be unfair if only one of their helpful posts counted by the forum.
In contrast, shit posters can spread their posts over different topics and all of their posts will be counted by the forum system.
10 shit posts are not equal to 1 good posts, I meant. So I think the best one is let it to managers to accept or reject posts in one topic per day.
AFAIK, some managers already reject posts in Mega spam topics.