It wasn't that he just talked about power ruling the world, that wasn't his main thing, he critiqued what people use it for and what the ultimate aim of it should be. He deepened our understanding of what power IS. For Nietzsche, most people possess a fake type of power, they simply use it to maintain "wretched complacency." I think the ultimate conclusion he made was that the most noble goal we can have is to overcome ourselves, and when power is used for that purpose, it is great. "What is great in man is that he is a bridge, not an end." If you are satisfied with complacency, with pleasure seeking modern society, you will hate him.