You're not "always right," by any means. I can't count the number of times I've had to ask forgiveness to God for being wrong, or my wife, for that matter
We don't "rule the world." This world, currently, is not our eternal home, so it's not of much interest to me or most of my friends to try and "rule the world."
And, most definitely, we can't do whatever we want. That's absurd.
I think the greatest benefit is getting to hear God tell you how much He thinks of you and how dear you are to Him. It's getting to know His Father's heart, which is so incredible and life-giving! It's getting to have a relationship with the God who created the universe.
Who's right and still is? "Christianity will vanish and shrink." Impossible. Although it will seem to, it never will. How can Christianity go away when Christ always has been and always will be?