For the time being, I believe nation-states, or maybe even multi-national alliances such as the EU (which are based on equal values) are the maximum we can realistically expect to work in reality. But the EU is at its limits already.
But in theory, expanding the idea of "rule of law, instead law of the stronger" Hobbes outlines on the international scale is not a bad idea. German philosopher Immanuel Kant wrote around 1800 already his treatize "About Eternal Peace" where he outlines such an idea. It's just not feasible for the time being, because you cannot get democracies and autocracies to agree on the same authority, for good reasons.