One of the episodes of Season 28 will be Kamp Krustier, and it's rumoured to be a sequel to the Season 4 episode Kamp Krusty. I was discussing this with a friend, and we don't know how this episode will be or how much it will complement the story of Kamp Krusty, but we both agreed that the Season 4 episode doesn't need a sequel. it had a good and justified ending, and the story played out well.
In my opinion, the episode that would need a sequel is Season 17's We're on the Road to D'oh-where. That episode had a very strange ending, with Marge and Homer arrested, Bart lost in Las Vegas and Lisa left to find a job to get money to free them both. i'd like to see a sequel of this episode: How Lisa (and maybe Maggie) managed to get a job, Homer and Marge's advetures in prison and Bart's adventures alone in Las Vegas.
What about your opinion? Is there other episodes that seems incomplete, and could use another 22 minutes to continue it's plot?