I think that while the merit system is good, the limits for rank upgrades are too high. I got 10 merits so I was able to upgrade to a Member, but upgrading to a Full member is an impossible task - I can't imagine how many excellent posts should I write to get another 90 merits. Has anyone succeeded to get so many merits yet?
You are right that it is hard to achieve but definitely not impossible. I remember one of the members getting 60-70 merits for a single thread. He might have become a full member now but I am not sure. My advice is that just keep making good quality posts as we may see some relaxation in rules in future.
Do we have to find a source and report our posts to get sime merits??
You can find out the merit sources if you see carefully the members giving highest number of merits. Admin has however mentioned in the official thread that the merit sources had not been made public as members may start begging for it.