Nations 3 and 4

Nation 3: Realism

Pretty much based on modern-day Europe.  I've got almost nothing to say about these guys, if only because they're not any given extreme, and thus have nothing interesting.  Hell, I'm not sure what their original niche or purpose is.  The whole goddamn world's Ace Combat like, down to not using the normal map, if I can swing it.  Anyway, not so much one nation as a loose confederation of several individual states organized under treaty and a central governing body similar to the UN or EU.  Although many laws and policies are shared between nations, each also maintains a high degree of independence.  All of the individual nations have long and storied histories, their own customs and cultures, and some still hold on to old rivalries.  Individual nations often show differences in various aspects of quality of life, industry, communications, technological development, and so-on.  The fairly new united government has yet to restructure to a single military, and thus each member state is responsible for its own defense, and still maintains its own armies. 

Nation 4: Technology

Technically not a nation at all, but a global megacorporation.  It officially lacks political power and influence, but it manages quite a lot of pull between lobbying and provision of goods and services.  It isn't the only such corporation on the planet, merely the largest and most successful.  It controls large areas of land, including the entire city in which is corporate headquarters are based, and has claim to a large number of potential "citizens."  The company HQ is a colossal arcology tower in the center of a city boasting a large population.  The tower has various unsavory nicknames such as "the Ivory Tower," and is considered one of the wonders of the modern world, as well as a symbol of corporate power and excess.  The corporation is best known for living on the bleeding edge of cybernetics technology, and is one of the few groups to actively encourage and embrace cybernetic augmentation.  It also has a hand in several military and weapons R&D projects, energy, medical research, and entertainment.  The entertainment branch has generated buzz in recent years for fielding a major pop idol who is, herself, a full-body cyborg. 

They don't have an official military, only private security forces.  Private security that's got enough manpower and equipment to make small countries nervous.  They have enough forces to police the entire city in which the HQ arcology resides, in addition to go out on public works and support missions, such as mist reclamation.  Like any good cyberpunk megacorporation, all the security and the large private forces are justified by what is as close to literal corporate warfare as possible.  Competitors attack to steal and destroy research data and the researchers who created it, and retaliatory attempts to do the same are common.  VIPs need the utmost of protection at all times, and policing a city and arcology with a population in the hundreds of thousands to millions is no small-time task.