I do not see it necessary to spend more effort or money to increase the duties of this organization. This new international government will either be brand new in 25 years, or it will still be in the process of being completed. This is not important, because main point is that things needed to be changed and things will be changed. The global scene will still be mostly dominated by a few states, but these states and all states will be much more low key, due to the growth of an economically unified world. On a national level, I think that governments will still be extremely powerful, but they will slowly be handing over the power to the corporations.
Money is the underlying issue here, and corporations are the ones who have it.
Governments will yield to these companies, but not entirely. Only 25 years will pass, and it is not possible for too much change to take place. The point is merely that corporations will continue to grow, and that governments will slowly weaken. Trade restrictions will be lessened, and single corporations will occupy many different states. Governments, as with the new international government, will have far less functions than they once had, and will be more focused on defense, infrastructure, and the justice department.