You can’t over-measure. The more time you invest in examining what is and is not working on your site, in your social media campaigns and with your marketing in general, the effective they will be.
One way to do that is to look beyond the bare minimums, like subscribers and bounce rates.
Instead, dive at least one level deeper into the data. So don’t just measure your audience in terms of subscribers, fans, visitors, etc. Break your audience down further into segments to find attributes that may lead you to insights about what kinds of customers are buying which of your products/services. And in turn, this can tell you which content resonates most with that segment. (You are aligning all your content with your various services, aren’t you?)
Similarly, track engagement in more detail. Can you assess sentiment? That old saw, “it doesn’t matter what they’re saying as long as they’re talking about you” may be true, but I wouldn’t count on it. Charting your audience’s engagement against how much of the activity can be characterized as positive, negative or neutral will lead to insights about changes in the market as they happen.
There’s really nothing fancy or complicated with looking at your metrics this way. The key is to interpret the numbers. Yes, there’s value to simply charting them over time and analyzing trends. But you stand to gain much more insight if you dig more deeply into what the raw data tells you.