Byzantine revival is naturally one of the more popular ideas on this site, but all things considered, even if the Greek Goose wasn't totally cooked, after the 1341-47 civil war they were very clearly in a tailspin, and more often than not IMO the Empire would have been conquered by someone.
That being the case, I am narrowing the prompt in two ways- first, using a PoD circa the Battle of Ankara, with Tamerlane and his successors finishing off the Ottomans completely, and secondly I am asking specifically who will be the most likely to conquer Constantinople; the Morea may or may not survive as an independent state.
For my money, I'd say either Tamerlane himself does the job (or his heirs) or either Hungary or Venice put the Empire out of its misery.
That being the case, I am narrowing the prompt in two ways- first, using a PoD circa the Battle of Ankara, with Tamerlane and his successors finishing off the Ottomans completely, and secondly I am asking specifically who will be the most likely to conquer Constantinople; the Morea may or may not survive as an independent state.
For my money, I'd say either Tamerlane himself does the job (or his heirs) or either Hungary or Venice put the Empire out of its misery.