I would like to see the R* (Star birthrate) AND Nh/Nl/Ni (habitable/life/intelligent) properly INTEGRATED over the very different star forming regions (and, if doing a "universe" estimate, for different galactic forms, spiral/eliptical).  The star density in central galactic regions is hundreds of times that in outer regions. As a result, the environment in the high density regions is probably less conducive to long-term life, being subject to many "nearby" life resetting events like supernovae and gamma ray bursts. Seems silly for scientists to use single galactic averages for these figures.