[Twan]

One thing has never been done : a dynamic modded game (= a game where a game master changes settings during play, technically possible but would need all players to dowload a mod each x turns, and would also be ultra exploitable by an abusive gm or ultra buggy with a gm doing errors). Anyway the possibilities in this area are fantastic and for the moment unexplored (ie : system where players customize their troops or create completely new units during play, scenarized game, stability system ala EU3 with penalties for nations breaking their treaties etc...).

Except that I think many kinds of original games have already been organized (modded nations, pretenders, etc... maps without indies, maps with many starting provinces, many kind of victory conditions)...