I was a mod on a couple of forums, including Marvel comics (their website forum). Modding is VERY hard, and can be very stressful. Sometimes the best thing to do is just rotate amongst the mods - not sure how many are here right now, but if a couple can take one week on, one week off, rotating with one or more teams of two, then it's not an everyday stress. Some sort of arrangement like that can lessen the pressure a bit.
Another thing you can try is assigning specific jobs, depending on what everyone's good at. If one is a good organizer, he can makes sure threads are in the right forums. If one or two are good referees, they can focus on keeping discussions civil. and so on and so forth.
Also - and this I'm saying from vast modding experience - it's best for moderators to stay out of heated debates as a mod may actually be responsible for escalating a situation. When you see things getting hot, step in and ask people to calm it down without taking sides. Being neutral is often the hardest thing for a moderator to do. I also found it best to warn a person of their conduct in private PM instead of in the thread because once you make it public everyone starts jumping in and taking sides. Sometimes it's best to publicly ignore an offense because it's more likely to be quickly forgot rather than be blown into a huge board meltdown. If a post has received a lot of complaints, warn the person in private, then comment publicly that the situation has been dealt with, and if necessary close the thread.
It really helps to keep board issues under control, and keeps tempers at bay. Doesn't work all the time, but it is helpful most of the time.
das