There are endless questions. You may think you have answers to all of them, but I don't see this as a feasible path. Far more practical to take control of national systems than to embark on a moon-shot global government design, especially given today's balance of power in favor of corporatism, and their control over the media. Finally, and to my mind most important, The World is simply too large a unit for us reasonably to expect democracy to function effectively there. The Greeks thought the city-state was the ideal size for autonomous democracy.
Democracy inherently works better at a smaller scale, rather than larger.
The larger the society, the more problematic it is to set up systems that enable such collaboration, the more difficult to keep them from becoming bureaucratic, remote, authoritarian, and corrupted by determined special interests. So the choice of scale, for democratic activism, is crucial. One can debate the virtues of various scales, but in today's world, given multinational corporations and all other factors, I firmly believe the national level is the most promising focus. Delegates would really be chartered to seek effective remedies to world hunger, poverty, human rights, pollution, etc. It's not a world government that's needed, it's governments which actively pursue the betterment of human welfare instead of corporate enrichment.