I'm a well read grad student who's bluntly honest about all things, although I try to be most honest about myself.
Obviously, Black Widow is the common aspect in all four issues, and she's paired up with four women from the Marvel universe: Amora the Enchantress, The Wasp, Mrs. Marvel and Storm to be specific. The stories range from Black Widow in her childhood to her stint as an Avenger, to her working directly for Nick Fury, to her working with Storm against gang members.
It was a nice, if limited, cross-section, of Widow's life and of the women in the Marvel universe.
It just was missing something that made it absolute magic for me, that pushed it into that five star spot. I'm glad I read it, though. So far, Marvel Unlimited is, overall, one of the most spectacular gifts I've given myself. And I'm going to save so much money in the long run!