I would really love to get into some good NRP. I am already going through some nation ideas, but have some questions. How realistic is the setting expected to be? You mention that the oxygen is hard to come by, so I assume we will have to justify how our people survive on other celestial bodies, but there are other problems than just getting oxygen and water, namely some moons have huge tidal forces and heating, magnetic storms and other fun things. So if we choose some planet or a moon to inhabit, do we have to be super realistic about its enviroment?
What about humans? I assume that in the year given the technology will be more advanced, so various implants, modifications or extensions to human body would be somewhat normal? What about longterm effects of living in lower (or higher) gravity environments. How big nations are we talking about approximately?