I mostly agree with you
However, the majority of the signature campaigns you implicitly refer to here are asking users to make up to 25 posts weekly at max, so 5 posts in the gambling sections of the forum seems to be a totally justified and quite reasonable amount. On the other side of the dice, though, the new Wolf.bet campaign sets the max number of posts to 40 which is essentially the same ratio (well, it is still somewhat higher but you get the point). To sum it up, 8 posts a week in the Gambling section would be a good start and in line with other campaigns