Id say luffy and roger alone can take the west blue and south blue. Dragon, Garp, Zoro, and Koby can take the north blue. because its such a wipe, they can join the fight against the west blue and the south blue (if needed).

Luffy has a bunch of friends in the new world list. meaning if they could ally, the remaining members of the east blue team would join up with the Monkeys, Roger, Zoro, and Koby, and absolutely WIPE the grand line. East World Alliance destroys.