LARP mechanics are incredibly personalised to the game. Everyone will have an opinion on them – they will like or loathe them depending on their own gameplay style, interests and how easy they personally find them to use. This means that when you get or give feedback, you will need to think about how personal it is. A lot of folks like rules-lite systems because they don’t have to remember as much — but players also flock in their thousands globally to World of Darkness games that use slightly modified forms of a full tabletop book selection. So different strokes for different folks.
Then there’s the not-so-small matter that what works in game, might not work in another due to differences in gameplay, antagonist design, length of the individual sessions, or focus of the sessions (i.e. political games have different needs to war games).
Have a Vision
Think about what you want to run. Think about the number of players in your game and whether Player Character versus Player Character actions will be a part of your game and in what way. Will the Game Masters be providing much content? Are their cast members providing NPCs?
Will the mechanics be primarily utility-oriented (unlocking certain areas of the game through hacking or lock picking) or primarily combat-oriented (which can typically be divided into damage types, crowd control types, healing types, and avoidance types)?
Is this a game you want people with very little prior experience to be able to just pick up and play? Or is this something where they will need to attend a workshop? You might not have many mechanics but if they’re complex and not very intuitive then they’ll also have their own experience requirements.
Think also about how many skills you have and how many players you’re likely to get. If every second person will have locksmith, you’re going to need an awful lot of locks. On the other hand, with 20 players each having 1 of 50 skills, you may be making content no one can access.