This is what I think season 2 will be about:
Plot:Coulson will be rebuilding S.H.I.E.L.D and using the black box Fury gave him to find missions and more secret bases,also Skye's Dad will be an antagonist.
Characters:All the main cast will return with Hawkeye appearing in at least 4 episodes with maybye MockingBird appearing,In the season finale an Avenger(Iron man or Captain America) will appear near the end of the programe.Other character's include Maria Hill,Nick Fury,Billy Koeing,Audrey Nathan,Donnie Gill,Franklin Hall,Glenn Talbot,"The first time I came down here was to lock up Johnny Horton" and more.
Tie-ins:With Guardians of the Galaxy coming out in cinema's I hope their is a tie-in with the movie like what the alien used to make the G.H drug is and what Sky and Raina are.
Post in the comments about what you think.