There's one simple metric for SETI progress that I would like to see and have always had trouble finding.

What is the radius within which SETI can exclude the existence of a civilization currently using Earth-like electromagnetic communications technology and how many star systems are believed to lie within that radius ? How will proposed SETI efforts expand that radius ?

I think this is kind of a key metric that could tell us a lot about how widespread technological civilizations might be in the galaxy.