Tripwire blog's The Top 10 Tips for Building an Effective Security Dashboard is an interesting collection of advice from several people. It's thought provoking, although I don't entirely agree with it.
Tip 2 'Sell success, not fear', mentions:
"For example, in the event that they cannot find personnel who come equipped with the skills needed to improve progress, security personnel can use dashboards to demonstrate the impact that well trained individuals could have on finding and resolving issues and threats, as well as to subsequently leverage that insight for training and cultivating available skills."
Although somewhat manipulative, metrics can indeed provide data supporting or justifying proposed security improvements, assuming that, somehow, someone has already decided what needs to be done ... and suitable metrics can be useful for that purpose too.
The thrust of tip 4 'Use compelling visualizations' is that the dashboard needs to be glossy: I agree dashboards should be professionally crafted and reasonably well presented but I feel their true value and utility has far more to do with the information content than the look.
Tip 9 'Thoroughly vet the information before it is presented' is an odd one. The advice to be ready to explain outliers and anomalies makes sense, but the implication of someone vetting the data before it goes to the dashboard is that it will be both delayed and sanitized. Hmmm.
Well, take a look for yourself and see what you make of the ten tips.