There wasn't much doubt that Agents of SHIELD would return since the ratings have stabilized and the audience has responded well to storylines that have crossed over often with Marvel's films. The current Inhumans arc doesn't just introduce the super-powered race before their eventual movie, it tied in directly with Avengers: Age of Ultron.
That Marvel and ABC were considering a spinoff starring Adrianne Palicki as Bobbi Morse and Nick Blood as Lance Hunter only showed their confidence. However, fan reaction the spinoff was lukewarm and the network decided it best to keep the characters in the flagship series. Agent Carter did solid numbers during its brief "event" run that had Hayley Atwell reprising her Captain America: The First Avenger role. Season Two will likely go further into Carter's role in creating the spy organization, SHIELD.
