You see when it comes to merits its not about your own evaluation but the people who are reading your posts. Several times I have made posts that based on my opinion, should attract merit but it won't happen while at the same time the ones I don't expect, I get merit that I will have to go through my merit history to have an understanding of which of my post actually earn the merit. So, do your bit on the minimum. I have seen a one line post earn a legit merit.

Another worthy to add is that, its not only posts that people have earn merit for. Some people have added value on the forum either by bursting some scamming behavior, doing some analyses of forum statistics, campaign managing effectively, engaging in legitimate business activities etc. Put all these together, you can get merit without having to be 100% coming from posts.