I was thinking about something like that.
To accomodate all possbile scenarios (e.g. border by sea, island countries, different shapes) the map would have to be player drawn - hence it's technically challenging. For now, I believe that, ultimately, the player's imagination does a much better job than any map generator I could come up with. That said, the map gen is the next logical step in expanding warsim, so I might try something.