I suppose the answer to my question has to be "all of them" since we are a Stack Exchange site.. but I'm still going to ask..
I suspect that not all of the metrics are intuitive. For example, if the "perfect" answer to a question already exists, should people be posting an "almost-perfect" answer simply to boost our answer ratio?
I guess my concern is that how we're assessed doesn't necessarily line up with how we ought to behave. Are there easy things we should be doing which would make the site "healthier?"
Also, I have no sense right now of how healthy is Blender.SE right, from the perspective of the people who decide whether we graduate from Beta, or get shut down. Is there somewhere we can look to get that information?