Shamrock declared he will subdue Elbaf. What is the plan? Killing all the giants so that the World Government gets an empty island? Doesn't matter, he is not the one that makes the decision. His superiors in Maryjoa, maybe his father, will tell him to leave. Shanks might be coming back, and Luffy and Zoro alone are too much. After what happened at Egghead, Luffy won't be underestimated. Dragon said the real battle would start when the Holy Knights get active. Would be anticlimatic if they get defeated a couple pages after they get active. Wouldn't have been the real war that Dragon foretold. Gunko will be defeated on the Moon, way later. She will be assigned to Caribou for protection. Caribou prayed to a god, that was surely not Blackbeard, it was Imu. Gunko likely serves him directly. She might have been who killed Cobra, as many have pointed out already. There is so much to her, she won't just go down a couple chapters after introduction.