>GS's consisted of caves connecting empty towns, the beasts, and Kanto
>RS was reading braille, Rayquaza, and the Battle Tower
>FLRG added the Sevii Islands to RBY's post-game
>DP was event mons, legendaries, and the entire Battle Zone
>BW was the legendaries, Battle Subway, sage hunt, and eastern Unova
Fixed.
XY's post-game is pretty bad. Every game after Gen 1 except for Hoenn has introduced entirely new areas for its post-game.