Stamina and extra effort
Idea 1: Running vertically up the wall would consume extra effort over time. This would allow players to jump off the wall to volley the ball.
Idea 2: A perfect tackle would restore 10% of lost stamina and a small amount of extra effort, making it easier to launch counter-attacks.
Idea 3: A third dribble would consume 50% of extra effort.
Idea 4: With the upcoming long-range shot, the ball would be faster and consume 75% of extra effort and 25% of stamina.
Idea 5: A perfect touch would grant 10% extra effort.
I think prioritizing mechanics of stamina loss and regeneration would allow for unprecedented gameplay depth.
This could be adjusted over time to find the optimal balance. With the increased stamina,
the game will be faster but also more punishing for those who don't manage their stamina well.