[Taqwus]

Perhaps there should be additional situational morale modifiers. Consider troops faced with a no-retreat do-or-die battle; would they not fight a bit more fervently than usual? Defending the national capital province would also have a similar effect... and in the case of a battle over the defender's /Last/ province, perhaps both sides should get a morale bonus (the attacker too, as they're looking at the possibility of inflicting a final defeat).
I could also see a negative modifier for starting in battle without being assigned to a specific commander, e.g. either because the commander was neutralized during the magical phase or because the unit was part of the province garrison only... but if -1 is the smallest magnitude it'll go that may be a bit harsh.