I think I'm one of those paranoid sob who scream like a little girl when he gets his backside handed to him. I was doing no skirmish (except to get the off new) until Chapter 7, Selv was basically a wakeup call and I was went nut trying to survive and started farming the skirmish. I got my Scout to lvl 20 before chapter 11 and by the time was was on 15 everything was maxed out.
I've just recenlty finished unlocking everyone's hidden potential. I'll look around for a list with all the data and if I can't find out I'll post one up to help everyone.
Some of the character are FAR better than others thanks to potential and the godly Awaken command.