Each trait half distributes four points between the four attributes (1 at 2 pts, 2 at 1 pt each, 1 with no pts). Each racial half distributes ten points across the attributes (2 at 4 pts, 1 at 2 pts, 1 at no pts...the image is wrong, but it's give an idea.). Each half gives an ability, which might be an action that can be taken at certain times, or a modifier that applies in certain circumstances. I don't know if we need anything more for the game at this time.
A character compares their total attribute to a difficulty threshold when the confront a mission; easy missions have a difficulty of 3, moderate missions are 6, hard missions are 9. Each mission has a specific attribute that is used to confront it.
The example character above would have no trouble contesting easy missions using combat, knowledge or skill. They'd need 1 point of bonus to confront a moderate mission using their skill attribute (this could automatic if the mission occurs near a "natural" location, it could be gained from equipment, or from specific situation cards played during the game).
Players can modify their own missions to make things easier, or modify other players missions to make things harder (or make it easier in exchange for a favour later in the game).
Now the trick is writing up the rules in a way so that they make sense.