What I've always enjoyed in a 24 hour MilSim game is when the game is proactively-driven. By that I mean you do not always have nice and neat objectives laid out for you before you hit the ground. Rather, you deploy your numbers, or portions of them and discover items of interest that get generated into tactically-relevant objectives that will benefit your team in the end. In other words, allow each team to establish their objectives with the primary focus remaining; the elimination of the opposing team.
This formula seems to function on it's own without a major requirement of referee involvement. The emergency radio channel, dispute guidelines, and timing coordination remains a constant, but it otherwise allows those who would be normally monitoring a game to participate as well. My two cents.