How would the trait system be enforced? By the players, or the GM? How would they come into play? I could imagine perhaps a sort of "Dungeon Master" route to this, where you'll present us a scenario/obstacle that only a few traits could be used to overcome. 

Example: The party needs to find a way into some ruin, and there is debris of some kind blocking the [i]obvious[/i] entrance. A character with a trait that grants strength could move it, but if none of us have strength, we would have to find a different entrance.

Yes?