I don't think anyone has yet discovered a perfect system. The current system, having survived this long, seems like the best system. It's easy to implement. However, its biggest drawback is that it encourages greed. You demand more. When one side gets more, the other side gets less. The gap widens, creating an imbalance. It's like in a tug-of-war game. The stronger side pulls as hard as they can, and when the balance is disrupted, the game ends.