Empire heroes are sadly lacking in ability to distinguish one hero from another and the general of the empire lord choice is much less interesting than the newer Huntsmaster and Arch Lector options.
For the Empire update in Thrones of Decay I suggest each of the following characters General of the Empire, Battle Wizard, Witch Hunter and Captain needs to have additional skills added to give the player meaningful options while using these characters.
I would also suggest that the Arch Lector and Warrior Priests gain additional skills buffing Flagellants perhaps taken from Volkmar but both the Arch Lector and Warrior Priest are in a much better place than the characters noted above.
For generals and captain I suggest something like this being added with three mutually exlusive skill lines each having its first point being accessable somewhere around level 5-10. Preferably these come with weapon changes for these characters but could also be merely attribute changes. Names and exact effects are suggestions.
Veteran Hero -> Character gains a greatsword weapon and appropriate offensive attribute changes.
Disciplined (requires Veteran Hero) (3 levels): Bonus recruit rank and upkeep reduction for infantry.
Steadfast (requires Veteran Hero) (1 level): Improves leadership aura size and hold the line aura.
Champion (requires Veteran Hero) (1 level): Bonus to defense and attack skill for character.
Bodyguard (requires Veteran Hero) (1 level): Greatswords gain guardian ability.
Artillerist -> Character gains a longrifle or repeater handgun and appropriate attribute changes.
Siege Engineer (requires Artillerist) (3 levels): Bonus recruit rank and upkeep reduction for artillery.
Quartermaster (requires Artillerist) (1 level): Restock ammunition ability.
Triangulation (requires Artillerist) (1 level): Bonus fire rate for artillery nearby.
Siege Lines (requires Artillerist) (1 level): Dig in like ability for artillery in army.
Knightly Orders -> improved armour and charge attributes and a lance while mounted.
Grand Master (requires Knightly Orders) Bonus recruit rank and upkeep reduction for knights.
First Sword (requires Knightly Orders): Bonus vs large for character, perhaps a bit of weapon skill as well.
Inner Circle (requires Knightly Orders): Knights in army gains charge bonus, bonus vs large and leadership.
For the witchhunter I would add something like this with not mutually exclusive skills all being accessible at rank 5-10.
Hunter of Cultists -> Bonus untainted in region.
Against the Armies of Darkness (requires Hunter of Cultists) (3 levels): Bonus leadership and weapon skill for army against forces of Chaos.
Sanctified Arms (requires HUnter of Cultists) (1 level): Witch Hunter gains magical ranged and melee attacks.
Root out Heresy (Requires Hunter of Cultists) (1 level): Public order penalty for large untainted bonus in region.
Hunter of Witches -> Large weapon strength bonus and ranged weapon strength bonus against magic users.
Determined Ignorance (Require: Hunter of Witches) (1 level): Witch Hunter spread magic resistance to small area.
Purge with Fire (Require: Hunter of Witches) (1 level): Witch Hunter gains fire melee and ranged attacks.
Seek the Witch (Require: Hunter of Witches) (1 level): Greatly reduced winds of magic in region.
Hunter of Vampires -> Witch Hunter becomes immune to psychology.
Strength of Faith (Require: Hunter of Vampires) (1 level): Witchhunter gains large weapon and ranged weapon strength bonus vs the undead.
Sigmar Protects (Require: Hunter of Vampires) (1 level): Whichhunter gains large ward save bonus when fighting the undead.
Foolish Perseverance (Require: Hunter of Vampires) (1 level): Witch Hunters army gains large corruption attrition resistance.
Wizards gain two mutually exlusive skill lines available somewhere around rank 5-10, as well as a few skills depending on their school of magic.
Researcher: Bonus to research rate.
Wise to the Winds (Requires Researcher) (3 levels): Small winds of magic bonus for army.
Artificer (Requires Researcher) (1 level): Improved magic find for army and income in region.
Teacher (Requires Researcher) (3 levels): Improved recruit rank of wizards in region.
Counselor (Requires Researcher) (3 levels): Bonus experience to characters in army.
Battle Wizard: Significant health and weapon strength bonus.
Arcane Combat (Requires Battle Wizard) (1 level): Reduced cost of buff and debuff spells.
Strength of Will (Requires Battle Wizard) (1 level): Increased duration of buff and debuff spells.
Champion (Requires Battle Wizard) (3 levels): Increased attack and defense skill.
Defensive Magic (Requires Battle Wizard) (3 levels): Increased ward save for wizard.
Call of the Wild (3 levels): Each adding a summon beast ability once per battle say Bats/Wolves/Bears or something.
Aura of Ferocity: Small weapon skill and weapon strength buff near the wizard.
Harvest of Souls: Improved winds of magic in region with each battle.
Terrifying: Cause terror.
Order of Light: Bonus public order and untainted in region.
Aura of Bravery: Improve leadership aura.
Order of Gold: Large armor bonus for wizard.
Alchemical Master: Bonus weapon strength to gunpowder units.
Healer: Bonus replenishment for armies in region and growth in local region.
Strong Life Force: Regeneration for wizard.
Celestial Order: Small bonus to income in region.
Chance Manipulation: Small area with small bonus to ward save around wizard.
Lucky Shot: Small area of accuracy bonus to ranged units.
Shadow Stride: Bonus to movement range of the character and any army he joins.
Hidden by Shadows: Bonus ambush defense and ambush chance.
Flaming Weapons: Bonus weapon strength and fire attacks for wizard.
Aura of Fire: Deals small amount of fire damage to enemies near him.
Ignite Weapons: Allies within small area gain fire attacks.