Brooklyn Nine-Nine is definitely one of my favorite ever sitcom. It's a show of pure comedy with humorous stories that are naturally delivered by the lovely actors and actresses, but also with a consistent storyline which a lot of sitcoms lack. The other thing I've noticed which makes this show better is the exclusion of laugh tracks. Although, laugh tracks do, to a certain extent, seem to make shows more hilarious and to a point where even if you don't understand a joke, you'd laugh. But no, this show has no cheats like that and amuses viewers with original content.
The show also does not rely on one-liners or simple jokes, and instead, make use of the characters' personalities and actions to entertain viewers, which is pretty smart. Some might think that entertainment with personalities do not last as they stay the same and eventually people would get tired of them. However, with the ongoing characters development, their personalities and stories are often changing, which makes the show so fresh all the time.