In the LARP I've been running for the past two years, I introduced an economy that I called Soul Notes. The idea behind felt pretty simple to me.
Originally the game that we based our LARP on used a series of skills that automatically worked, but could only be used once per game. If you wanted to use "diplomacy", you had to have an appropriate skill card with your name on it. You flashed the card in the middle of a deal-making session, and either the opponent agreed with you or they lost a life. It all felt a bit heavy handed and trite to me; so when we broke away, I shook things up a bit.
My variant developed an "economy of fate" which gave everyone 5 "soul notes". These notes reflected agency in the world, and were used with a range of skills, including Diplomacy, Picking Locks, Escape, and other things like activating magic items. A player could indicate how much they of this fate energy they want to infuse their action with, while their target may choose to accept the incoming action (and claim the staked "soul notes"), or could deny the action by offering a matching number of "soul notes" back to the active character. If a player found that their character was targeted by multiple incoming actions, they might accept their fate, gradually building up fate energy as other people use up theirs...or they might use up their fate energy by blocking everything until they run out of notes. More often than not, they'd spend notes to avoid the worst, accept their fate if things don't impact too much on their story, or spend a few to activate their own powers.
Adult players, and mature players, understood it intuitively. A lot of our younger players, and those who just came along for boffer action, never quite got it.
I've now had the chance to rebuild something new, I'm thinking of a technique that I saw a LARP using many years ago. The basic idea would be to give every character a playing card. The when they tried to act against each other, they'd just reveal their cards...high card would win...then cards would be swapped. Characters would not be able to confront the same opponent before they had confronted someone else (this heightens the flow of cards through the game and stops a continuous back-and-forward between the same two characters for the duration of the game.
Another way to make things a bit more dynamic might be to give every character a pair of playing cards. Then they can choose to play their higher card for a better chance of getting their way in a conflict, or play the lower card to save their high card for later.
Similarly, I've been thinking of adding nuance to the system by allowing characters who have "mastered" their skills to gain +2 to the face vale of the card when comparing it (but the swap still occurs after the action), and possibly some kind of effect that gives a magnified result if one character's card is more than twice as high as their opponent.