If you have a game design idea, please think about whether it is a rule idea, an AI idea or a macromanagement idea. The chance of giving the nations different identities by the wonders they built is wasted. The military unit concept is plain and unrealistic. New technologies always make the same predetermined units available - equal for all nations. The game has no worthy end.
Nations can simply trade their technologies.
The more nations share their techs, the faster they will advance in concert. Outsiders fall behind. All advanced nations share their technologies. There's no considerable scientific lead, no reward for being better. Maybe we'll have a big AI championship then and a strength rating system.