A very cool feature would be an option to view time lapse game progressions of already completed games. That way one could "watch" games of other players they hope to learn from. Plus, it would simply be fun to replay how you were able to trounce opponents in a particularly memorable game. Fog of war would be lifted, of course.
The closest that we can come to this right now is the Handy Game History script. Because of the limited information in the game log, actual troop counts cannot be replicated, but you can watch as territories change hands.