The main metric I like to look at when evaluating post quality is not how many people saw it exactly, but rather how many times it was shared, either re-tweets, shares, or however Facebook calculates its "virality" metric. We want folks to share our posts for many reasons, not the least of which is that is gets your brand in front of eyeballs that aren't already following us, so I look at what posts are popular to share in the community we already have, and try to do more posts like that.
For example, your recent post was only shared twice, but from those two shares, that post was seen by twice the number of people than actually like our page. What was it that made that one popular? I'm thinking the fact that it is part expert commentary, and part a fun sort of window into your family life.