Byzantium is actually less niche this time around because even though historically they died, at least they had a realistic chance to recover starting in 1337 unlike in 1444 and it pains me to see that they did not consider expanding it into the early modern era with events around the byzantines replacing the ottomans as the main boogeyman of the east in such a timeline. I do get what you mean though, if the spain dlc is this undercooked where it only covers like the beggining then the game is pretty much done for.