Present Late Era for SV begins in 1311. It is about 140 years ( 280 turns! ) before the use of arquebuse and the " official " end of Middle Age ( fall of Constantinople and end of the Hundred Years War ). That is 181 years ( 362 turns! ) before the discovery of the New World.
A careful player would need a lot less than 200 turns to reach vistory conditions, but that will last much more than 200 playing hours, which will take some real life monthes for most of us.
Thus there is almost no chance to play that great mod with others units than those used when beginning. Nevertheless vanilla M2TW runs until 1530, allowing the use of fire arms, Renaissance units and New World countries.
Is it not possible to supply a Later Era or Renaissance mod for SV, which would start in 1453?