If I were God of the World, I would model the problem as more of a River Crossing Puzzle. How do you get things moving along when everyone on the boat wants to kill each other? Segregation! Resettling humanity mapped over a giant Venn diagram is trivial once we are all uploaded, but it also runs into ethical problems; just as voting and enacting the will of the majority (or some version thereof) is problematic, so is setting up the world so that the oppressor and the oppressee will never be allowed meet. However, in my experience people are much happier with rules like "you can't go there" and much less happier with rules like "you have to do what that guy wants". This is probably due to our longstanding tradition of private property.

This makes some assumptions as to what the next world will look like, but I think that it is a likely outcome -- it is always much easier to send the kids to their rooms than to hold a family court, and I think a cost/benefit analysis would almost surely show that it is not worth trying to sort out all human problems as one big happy group.

Of course, this assumes that we don't do something crazy like include democracy and unity of the human race as terminal values.