There are literally a plethora of areas that could add to the game, most of which all lie on Eorzea itself, without even considering the other kingdoms and landmasses that are mentioned by NPCs or in the game's lore.

Abalathia's Spine, The Farreach, Gir Abania, Xelphatol, Paglith'An, O'Ghomoro(not to be confused with the stronghold), Dravania, and plenty of named islands and other landmasses all over.

You'll get your beach areas eventually.