Oh yes — that is cool idea.
Also, by adding a whole-force morale breakpoint, it could open up new strategies for the player, who could try for a psychological/morale victory even when outnumbered or out-muscled (by Orcs, for example). Maybe some traits/skills could be added to expand this idea?
I also wonder about adding a “fighting retreat” option for the player — this would allow to quit a battle without, for example, losing most (or all) “brothers”?