@NecroKnight The story's still in the initial phase. We're close to wrapping up the wedding celebration then moving on to more shall we say Game of Thronesy parts of the story.
Of the Great Houses, the Tullys, Starks, Martells, and Greyjoys are open. You can also make characters from any of the other notable families or minor houses. And you can play a wide variety of character types; holy men, bards, mercenaries, merchants, scholars, sailors, and warriors from any of the seven kingdoms in Westeros. There's also the Stepstones, the newly integrated Wildlings, and a bunch of Essosi-type characters who would settle in Westeros or travel to the continent seeking their fortunes. Alchemists, Red Priests, Maesters, Septons, Knights of the Green Hand, all of these are possible.