Lessons learned from this year's Z-Day:
Upgrade exterminate some at the beginning to deal with the trolls and zombie farms.
Any nations that are focusing on building zombies, exterminate, and any that are researching/need help, heal.
That extra shot at zero zombies kept them from getting new zombies (at least until they get hit by trolls/zombie farms)
and we need to figure out what to do with countries that don't help (or act at all)