One of the problems that you run into in a LARP that you don't generally run into around the table is the afflictio of too many Main characters. In every gaming group most of the people at the table are main characters. Some players like to hang back and crush monsters, or work the puzzles, or just listen to some good narration. There are ways to get them into the main stream and spot light, but it's not necessarily their thing. In a LARP you've got a whole field of players, and with rare exception, every one wants to be the hero.
If you've ever listened to a bunch of people's booring fucking origin stories this is pretty evident. They are rare half vampire/werewolf hybrids from space who trained at kung fu monestaries for centuries even though they don't really fight very well. Get ten of these guys together and leave them to their own devices and hilarity ensues.
One of the easiest ways to deal with it is not to deal with it. You write the quest without considering anyone's background or perspective. You pointedly ignore any self centered drama. This works great for the quest, but does it satisfy the players? Deep down probably not, and those poor emo kids are going to feel some ennui about the whole thing.
Another technique is to stoke them up about their hero hood and get a high 5, then pointedly ignore it. This will accomplish the same thing questwize but will trick most players into thinking their special little snowflake was properly considered in the grand scheme of things.
Or you can cater to everyone individually. This is exhausting. In large groups you can just cater to the leaders, and get by pretty swell. Someone might blog about it later, or write an indie song, but in generall it won't effect your Quest at all.
One of the lessons I've learned from some of the high end pay to play LARPS, like Nero, or Steam and Cinders is not to worry about it. Just work on the setting, get out of the way of the players, provide opportunities to role play, use funny voices, and let the players handle that demographic all by themselves. Quiet players will rise to the front when warrented, and support the mains the rest of the time. Leaders will lead, followers will follow. You need a good staff for this, so take some extra time and educate your minions before the quest begins. Pay attention to what the players are doing. Make adjustments based on their needs, and things should turn out ok.
Do not throw a fit because your precious main bad guy isn't the prettiest.