I don't think playing Byzantium will be that difficult. Really, it's about getting the trade flowing, flirting with the Genoese and grabbing a few minors. Ohh... and praying to the Hellenic gods that the ottomans give you more time. If the Timurids are able to push into the border with the ottomans or the mamluks attack, then you are in the perfect position to grab yourself the balkans back.
We will have to see what I do in my lp. It really does seem like it will be Byzantium.