I think it was terrible directing to off Jimmy. This season spent episode after episode building a character, Jimmy, to a point where the viewer finally understood his background and who he was. Jimmy in Season 1 was just a random character with some supposed baggage that was never explained. Jimmy in Season 2 was the main character of the show, even moreso than Nucky I felt, and for the matter, more interesting. To end it with him getting killed, what happens next season? There was so much effort put into not only building up Jimmy, but the characters surrounding him. Now, what do you do with Richard Harrow? Does he take over Jimmy's position as Nucky's foil? Or does he got ape **** crazy and try to kill everyone associated with Nucky? The Commodore is dead already. What about Jimmy's mother? She became very intriguing, now what do you do with her? How does she remain a part of the plot?
By killing Jimmy, basically 5 characters have no part of the show or are dead(Jimmy, Jimmy's mother, Angela, Richard, and the Commodore). So next season, the first few episodes at least will be to build new characters or expand on current characters (Horvitz, Capone, Charlie, etc). Unless there is even more focus on Margaret, which in my opinion will be very frustrating. Hopefully the plot continues to be exciting, but I am very disappointed by the way it ended this season.