LARP groups are tricky, moderating LARPs is trickier. Especially boffer LARPs, or those where real-world physical representation of character statistics exists.
In a tabletop situation, there's an automatic degree of separation. One character might be more brawny than another, ons character might have more knowledge of certain obscure subject areas...and this can all be governed (to varying degrees of success) by rules and dice rolls. It gets murkier when statistics governing charisma or social interaction are considered, when one introverted gamer is trying to portray an outgping character with massive charisma, but even then the player can take on an authorial stance (describing what the character does), rather than an actor stance (and actually role-playing the sitiation by saying the lines and fully engaging the dialogue).
It gets harder to do this in boffer-style LARP, not only because it is expected for players to embody their characters from a social standpoint, but because a part of the whole experience involves players doing the fighting for their characters, as well as the solving of puzzles and engagement of other elements of play.
For a character to be an expert fighter, you've got two options, and both have their detractors. First, you can train the players to be better fighters. I know a number of LARPs that run weekly, or even twice weekly swordplay sessions and martial arts classes to increase the fitness, strategy, and combat prowess of their members. This is great for immersion, players know how to hit safely, effectively, cinematically. It's not so good for players with busy lives who should be progressing their characters at the same rate as those other characters with players who do have time to attend those regular training sessions. In some cases it's all or nothing, either you attend the regular training sessions or your character (and every other character you'll ever play) falls behind those who dedicate their time/lives/money to the game.
Second, we can't grant super powers, but we can introduce rules to the game that hamper one group of players to effectively give advantages to others. This might include allowing a player to make a call like "disarm", "shield-break", or "sniper", which then has to be acted out by the target of the call. It stretches immersion a bit, and even breaks it for those who have trouble with imagination in games (such as those who call it re-enactment rather than LARP). Here's where rule systems come in, giving different characters different ways to manipulate one another according to the elements of the in-game narrative. Even something as simple as "hit points" can be looked at in this way, one player gets to keep swinging while another has to mimic being knocked out or killed.
There's a middle road, but that requires balancing lots of different factors. Many LARPs might have statistically identical characters, but if one player has a sword that's 15cm longer, that could lead to a reach advantage that unfairly gives one player's character the edge.
That leads me to what I was doing today, trying to find a middle road when incorporating NERF equipment into a post apocalyptic LARP with foam weapons and LARP archery gear.
Different guns have different rates of fire, ranges, accuracy, and ammo capacity. Many LARPs would reduce them to two or three categories and assign a common price to each, some might even ignore costs or categories and simply call them "firearms" which anyone can own or fire if they possess the right proficiency, but today's testing showed some massive differences between weapons which I might have otherwise considered similar in effectiveness before that testing occurred.
There's still a lot to think about on this, but important steps were taken today and it feels like they were in the right direction.