The length does not directly effects the show's quality in general, but it effects the writers' stamina.
Most of the returns of previous characters, such as Iron Will and Daring Do, are pointless.
-Some episodes are copies of other episodes. Forever Filly is too similar to Sisterhooves Social.
Some episodes are filler, like Triple Threat, Hard to say anything and Secrets and Pies.
Pinkie Pie only appears just to be annoying or creepy, like Secrets and Pies.
-The Starlight episodes are misleading, confusing and ridiculous. It's like the random crits of Team Fortress 2. It's unfair.
I'm not sure what my least favourite episode of the season is. Either Celestial Advice, All bottled up, Rock solid friendship or A royal problem. Some days I dislike one episode more than the rest and other days I do the same thing with another episode. But basically these 4 are my least favourite episodes in the whole season.
I think I just finished the season 7 because by the time I went back to the show last year I just didn't care about the story and the characters. If I liked an episode, I could just say it. If I didn't like an episode, I could point out its problems, ignore the episode and then move on.
Having new writers isn't a bad thing though, it's really what the new ones bring forward to the table. A lot of the times, you can't expect the same writers to stay on board a project for so long, like say have Conan O'Brien stay a writer for The Simpsons for all 30+ of its seasons. If the new writers managed to crank out some fresh good episodes then that's that and if they submit in crap, then oh well.
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