If you can only find 3 merit worthy posts in a month, then you shouldn't be a merit source in my opinion. I often find more than 3 in a day, but I can still end the day with a few source merits available for the next day's reading. I try to keep my personal sMerits for rewarding Fit to Talk projects that are moved into Bitcoin Talk, but this has been a bit slow recently, so I've got a total approaching 200 sMeits waiting for some good political translation posts.

Also, I think it would be a bit excessive to give a brand new member 50 points for his first post. I would rather give one or two points each to 25-50 new members to encourage them.