The changes I've made to the Thunderbolts pertain to their membership. If you've remembered, the older version of their lore is their Asian superiority beliefs. However, I've changed that a bit to their leader, Junichiro Nakamura, believing he is the true heir to the long-dead Mongolian emperor, Genghis Kahn, and that he will unite the world under the thunderbolts flag. They have operatives in all sorts of war-torn countries, notably most of the Middle East, Russia, Ukraine, Mongolia, Taiwan China, Japan (obviously), Romania, Czech republic, Turkey, Canada, the USA, Mexico, Brazil, and Argentina. They are able to stay secretive due to Junichiro's high political position allowing him to cover his and the Thunderbolt's tracks.