Re: How many of the merits source are doing what Theymos Said?
. I must say that before merits source be given to application they should try to know their activities, I mean physically task or home chores which is very hard for those who are wanting to become source, but if they can prove otherwise then they should be added as one and monitor them how they work or becoming that active to the community.
I would also add weekly meeting with theymos to report which posts received merits. 
Being merit source is a voluntary task not a paying job for whatever they do so let's not make it too complicated. And the thread you're talking about is just looking for ideas to bring back the merit sources in action since many became inactive and no new sources were added for a while.
Not criticizing the local board users or anyone if I am not wrong.