Episode 15 was great with Sunohara trying to get Tomoya play Basket and Nagisa thinking he was gay.
Episode 16 had the basketball scene, probably one of the best scene in the anime.
Episode 17 had this gif and Tomoyo being awesome.
Episode 18 had even more Tomoyo being awesome and Kyou losing the game.
Episode 19 had GARISA and better animation as usual
Episode 20 had the great and very heartwarming picnic scene.
Episode 21 and 22 were a pretty good 2 partner final with an epic speech from Akio
Episode 23 was probably the best episode in the show.
It actually got much better after Kotomi's arc, those who disagree probably fap to little retarded and dying moebleobs or something.