This could be troublesome. I mean, the crew of Serenity fighting for the crown in Westeros, and. . . eeh. . . a whole bunch of peoples, some liking each other, some wanting to kill each other, piloting the Serenity?
Now, I have no worries about Mal and his gang beating the crap out of everything in Westeros (and beyond), since, you know, they have River. I do on the other hand worry about how the characters from Game of Thrones would make it in a space ship. ESPECIALLY one which is almost falling apart at its best. When half of them want to kill the other half (ok, not really, but still), and none of them have seen a more technologically advanced vehicle than a boat before. <.<