(there must be a lenght requirements to be merited automatically, I think all can notice a long post if its a spam post/trash then if everyone report a trash post it can be automatically deleted).
you cannot judge a topic based on how many paragraphs contain the topic or how long it is written. If the number of words becomes a benchmark of merit giving, it will not change anything. Giving merit should be based on the quality of the topics that forum members write or a post they create, be it a long, or short, solid and clear topic. While the topic provides new and useful information, other members will certainly not hesitate to give you merit, not to mention the moderators in each topic.