Yeah, frankly the writers put themselves in something of a hole regarding more bestial player races. While I personally would love to see them, given the human/beastmen divide it makes those races a little harder to justify. If an equally bestial race counts as a human instead of a beastman, why do they? And sadly there apparently isn't much Japanese demand for such characters. Still, there is always reason to hope! If they did add Burmecians I'd guess it would be in a more FFIX themed expansion than Return to Ivalice though. Maybe when we get to meet the IX legion?