This would be neat, but it would require battles to span over in-game time, which currently they do not. It would require implementing a battle-combat time not unlike that of Mount & Blade, where groups could join combat midway, including yourself; however, this might cause several issues regarding difficulty (suddenly you aren't fighting that lone buffalo, because the pirate assault fleet wanted a scoop of that icecream), not to mention possible difficulties involving setting up how the battle-time versus oververse-time would relate to eachother.