Yall pretty much covered it all. Id argue some of the subjects have more to do with training and time with your dog vs breeding quality.
IMO (not including the things I train)
1. Hard, cant let go
2. Speed / endurance
3. Smart enough to let go and not drown on a hog, or heat stroke on a broken bay. (Ive seen several good pits drown on a stuck hog) never seen any other breed of cd do that but it was such a waste
4. ear dog 90% of the time, certain situations understood.
And dont break bays!