Bizarro Episode: Episodes 15 and 22, in particular the end of the first one with the card-puking. The second one is justified due to most of it being All Just a Dream. As both featured supporting characters of the episode, Tenko and Momoka, appear in the finale, neither can truly count as a Big Lipped Alligator Moment episode.
Covered Up: Some non-Japanese viewers may not know this, but while the songs featured in the show (that aren't the ending theme) were taken from the game, they're not the same versions heard in the game. The versions heard in the anime are covers performed by three of the members of S/Mileage in character as Lilpri (both in the show, and onstage in real life).
Ear Worm: Every song, in particular the ones Lilpri sings.
Fridge Logic: Why does Leila have a Japanese family name if her father is Italian?
Maybe her parents are divorced because of Marco's job?