Morale is always a tricky one to model in a Wargame.
Moving and shooting can easily be statistically determined but as to how your Warriors feel God only knows!
The way Morale has been modelled in Whores Blade 20,000 is each Warband has a store of Courage points. These points go down after particularly successful Attacks are made against the Warband and Warriors die.
However the points can also be expended voluntarily to reroll a dice through heroic effort.
Morale is thus a balancing act. Do you conserve points from loss or risk them to change the course of fortune? The choice is yours!