Disclaimer 1. This is Drac's opinion, it is not humble, it works for him. YMMV.
Disclaimer 2. This is impossible to write without sounding condescending. If you find it insulting then stop reading and click this http://www.badgerbadgerbadger.com link
You need to evaluate LARP this way, look at what you are doing and go: "at the end of the day, does the fun I am having justify the time/money/effort I am putting in to this?"
You are investing money/effort in kit, you are investing money and time in travelling to and attending the event. This can be used for : other hobbys you enjoy, overtime to make more money, relaxing with a cocktail etc... If you are not enjoying the investment, then why are you doing it?
Question 2: Does my method of having fun spoil the game for other players. This is best summerised by zombie LARP: "Am I being a dick Out of Character?" Being a dick In Character is part of playing the game, being a dick out of character is just being a dick to other players (as opposed to other characters).
If you can answer yes to question 1 and no to question 2 then seriously, who is anyone else to dictate or comment on how you want to have fun? For any the times when you are nervous as to how other people are preceiving you and your actions, just remember that, it's your money/time/effort for your hobby, it's up to you how you choose to spend the time.
Spend it doing things you enjoy and avoiding things you don't. This includes very much what sort of things you do in LARP. A recuring pattern with me is that my characters avoid/are oblivious to relationships, this is because I have enough trouble with that in real life, I don't want to add that stress to my hobby.
Reiterate rule 1 to yourself then explain the facts of life to your character. Those facts being that they may think that their purpose in life is to save the world/achieve ultimate cosmic power, in actual fact the sole purpose in their existence is to allow you to enjoy your LARP. If they don't like that, then they can easily be replaced by a new imaginary friend who is more complient to the management!
Have your character change, come to an epiphany, and conciously decide that whatever thing they were doing that was not fun or stopped you having fun is going to stop.
Remember rule 1. Rule 1 has a colerary: you cannot provide fun for other people. LARP is a social hobby, we like interacting with our friends, when things we do provide fun for our friends, that is fantastic and the cycle feeds back on itself. However our friends have to understand rule 1, and that they need to be doing things that they enjoy, and that you cannot be expected to provide enjoyment for them. If they want enjoyment provided for them, that is called the service industry and they have to pay people for it, but will be able to find a company that specialises in providing fun in exchange for cash.
If you are worried, have a word with them OC, "look guys, I know that when I was doing X it really helped the group, but it's just not fun for me." The reaction breakdown will go like this:
In my opinion, the 1% are guilty of "being a dick OC", remembering rule 1, ask yourself, "are these the sort of people I want to be playing with, or is it time I moved on?"
Do have a talk with your larp friends before you jack it in, odds are good they will be supportive and might be able to suggest to you some ways you can enjoy things more.
Don't be afraid to play a character that is basically you in a silly costume.
You will find that over time your character will naturally part company with you because they will do things that you don't: join cults, have all their friends murdered, save the world etc... Those things will naturally change them until you find you are able to think as them without having to force it or worry about IC/OC emotions and divide.
Every time I have started with a very tight and rigid concept of "this is my character and this is how they think" the amount of doublethink has driven me mad and eventually been dropped. I have never found a better way to get a character personality than to play them for an event or 2 and let them diverge from me naturally.
My easy tip for playing characters that are not you, is to make them you, but with one factor that is more dominant. This is often easy to decide based on any cultural/racial brief or a very short backstory. You will find that one or 2 personality enhancements will produce a surprisingly large change while at the same time being easy for you to manage. Over time you can add more detail and more changes, as the character naturally grows.
Example: Yoshikazu was heir to a clan. So for him I racked up my sense of Duty to the exclusion of all else, from the Kamakuran briefing I added to that a desire never to show emotion and I got someone who was radically different from my previous maelstrom character. 2 events down the line and events totally changed him again.
Conflict is an established part of most LARP games, so its unlikely that you will be able to avoid it completely, this is kinda where "playing someone who is you in a silly hat" comes in, make your characters natural reaction to avoid conflict if you don't want it.
While you will still get some, the conflict bunny's will mostly ignore you from their conflicts: conflict games are by far the most fun when the other side is playing them right back, if you are not playing their game it's not fun for them so they will look for someone who is.
It was once suggested that at Maelstrom there are probably about 50 active conflict players on the field stabbing each other with merry abandon. Everyone else is playing 500 NPC's to them - the population of a small fictional town who are there and going about their lives and so providing: challenge, cover, alibies, background, victims, marks. Without those 500 players wgo are not stabbing each other the game might as well be dump everyone in a pit and fight to the death.
Rules of thumb:
The more you do it with the showy character, the easier it becomes with others. Practice makes perfect.
For most systems, stats in conflict are actually vastly secondary to being willing to kick off and have conflict. Saying "we'll just wait until we have X" is a trap to fall into, because there is always Y and Z afterwards. Being willing to get stuck in is much more important, maybe you will lose, but that's half the fun - don't be afraid to get into a conflict and lose - at the end of the day the conclusion is only a small part of the story, it's the journey there that is the bulk of it and if you get some awesome roleplay or really cool fight out of it, then that sounds like the character probably fulfilled their purpose.
Using me as an example: Yoshikazu was a combat death machine: minimum of 15 hits, triple, immunities, sorcery. Bleeder was usually 5 hits and single. Bleeder killed vastly more people than Yoshikazu as Yoshi was an assassin who was carefully hunting his targets and so not very kick-offish, bleeder kicked off at most opportunities.
I came to Maelstrom on an invite from some warwick friends and played with them for 2 years, I had a choice to join Raid Hive and play with some different people - it was scary, but found that actually they were friendly, awesome and willing to share and improve my roleplay ability.
Borris kicked the bucket and I joined Havocstan, once again, fear of joining vastly outweighed eventual issues. I can't think of any better advice for this one than you really have to grit your teeth and force yourself. Pick a group of people who you think like similar game and get stuck in joining them - once you climb the inital mountain, skiing down is much easier than it looks.
Have a word OC "I want to join you guys, this is what I want to do, will it fit?" then go for it. You can get to know them OC as your character gets to know them IC, and in the end you get a new collection of friends.