Guidelines for writing rules

About half of a character's dice should be useful for something, on average.

A card should have 2-3 rules.

Concept cards:

Concept Rules should be useful about two-thirds of the time at their core competency: 1-2=no effect; 3-5=average effect; 6=doubled effect

Secondary rules on a Concept card should be 1-3=no effect; 4-6=average effect

Schtick cards:

At least one Rule on a Schtick card should overcome a specific class of challenge 50% of the time, e.g. a physical challenge or a social challenge.

Twist cards:

Twists aren't meant to be straight disadvantages.  They are meant to be plot complications that involve a player character in the game.  They should compel player actions or eat dice half the time, and provide the player with some unique ability the other half.  For example, a player might be hindered in combat with a particular type of opponent but also be able to repel that opponent under specific circumstances.

Combat:

inflict or avert can add up very fast.  Combat-focused schticks and combative concepts can conceivably stack 3 or 4 dice worth of damage on really good rolls.

To lengthen a fight, provide automatic avert or unlock effects to all combatants.