"Agents of S.H.I.E.L.D." is becoming frustratingly too much like a CBS procedural. This is set in the Marvel Cinematic Universe, and I think the viewers are going to demand more than a new case every week with a few minutes of exposition and character development thrown in from time to time.
Joss Whedon gave us the opportunity to celebrate our nerdiness. He could have delved deep into the lore and introduced obscure comic book characters, but he didn't. Instead he let us enjoy our current superhero knowledge.