Personally, I don't think that reduction in rank is a good idea either
This doesn't feel quite right since instead of a number of posts made on the forum, we would essentially have a number of posts made in specific boards. Bumping old threads could be prevented by locking them, but this wouldn't in the least prevent from creating new ones. We already have two multi page threads about Gold vs Bitcoin in the Economics section, totally useless each. In fact, not counting posts in them would only lead to creating more such threads
about tread that is something different you will always have 2 that are same or similar with topic this can be reduced yes
in gambling you have something completely different most are based on sport and certain league so this is hard
on other section i dont know how it is i didnt see but the fact is for this is will take time for it