Your Protagonist's Story Must Drive the Plot

 I think I've realised my biggest pet peeve with long arc storytelling or any for that matter. When there is no clear protagonist or that the there is one, but he clearly isn't the one that the plot drives. I remember one of my first full feature scripts I wrote at film school, my teacher, Ben, pointed out to me that the secondary Han Solo-esque character was the one "doing" all the stuff in the story and the Luke-esque protagonist despite being the foreground of the story was not driving the plot.

To a certain extent it's a problem I have with Game of Thrones, but more with shows like this season on Arrow, Oliver has had no real arc whereas the secondary characters have - especially coming of last season where the story arc was so strong. The season 2 of Orange is the New Black saw Piper basically removed from the foreground of the story entirely. The Walking Dead seems to hop scotch around this all the time, where Rick Grimes drives the plot until well... He's randomly not.

Ensemble cast storytelling is fine but I feel if the audience doesn't have a protagonist's story to drive the plot, the story and the plot become disconnected and you feel like you're watching two completely different movies/series.

My other pet peeve is M Nights Last Airbender... But I just f-ing hate that flick and will express any chance to tell the world.