Made some comments in another thread not seeing this one.
I would give the premiere a C-. They tried to keep the characters and the topics 'Harmon-esque', but they didn't keep the humor that way at all.
Jeff acted like Jeff, Brita acted like Brita, Abed acted like Abed...but the humor was just a string of quirk-driven gags, rather than being driven by the characters' emotional state and psychological history.
Also they kept up setting themselves up for great opportunities for zaniness, and not doing anything with them. The Dean sets up a battle royale to make students fight it out to get into the fluff class -- but they don't do anything that funny with it. Annie goes to play pranks on the Dean -- and all they can think of is to put popcorn in his car. These are both serious creative whiffs.
Then they had irritating facepalm moments like Brita and Troy fighting in the fountain then 'learning a lesson' that were just not funny at all.
Maybe the problem is they tried to have both an A plot and a B plot instead of just committing wholesale to one crazy premise, so they didn't have enough time to do either justice.