I have a question about the Injury mechanics; I haven't seen them add much to in-session play so far - are the bits about being taken out of the action on pages 12, 15 and 19 really necessary? They just seem like a threat to remove PC agency from the end of the game. As it is, I think the HOLD mechanic provides plenty of tension as we get to the Moment of Truth in the game.
That said, I really like how Injuries (and Scars) have some nice bite for campaign play though.
Afterthought: I wonder if giving players an additional campaign-level mechanic to ameliorate Scars would be fun (maybe by having them take additional Troubles)?