Right now there isn't a lot of faction differentiation when it comes to tactical combat. This leads combat to be simple and repetitive. A relatively easy way to fix this is to simply add more traits, so I have thought up some traits that would make races more unique and also make combat more interesting. These traits would be available to both troops and champions. Allowing champions of different races to feel more unique as well. I have tried to stick to lore as much as possible. I have also tried to design these traits so that they give each faction a different feel or strategy in combat. I would love to hear any ideas other people have as well.

Pariden

Use shards and mana to boost troops. An idea is that they can get traits that allow them to cast buffs on themselves, instead of straight up stat boosts.

Conduct: Allows unit to cast Conduct which strikes for their normal damage plus 1 lightning damage per shard. Removes Noble Legacy buff and can only be use once per combat.

Proud: Unit's initiative cannot be altered by enemy abilities or spells.

Enliven: Allows unit to caste heal on itself.

Quickening: Allows unit to caste haste on itself.

Altar

All troops are flexible and elite.

Hero's Chance: Unlocks a special attack that strikes for +1 accuracy per level, and +2 armour penetration per level.  

Avenger: +15% damage to Empire units.

Hero's Stand: Unlocks ability that grants +2 counterattacks and + 1 per level defence when defending, for 2 turns. 

Gilden

Tough and hard to kill troops. Have resistance to magic.

Stubborn: When knocked below 50% health unit becomes invulnerable for 1 turn.

Breaker: +15% armor penetration.

Weathered: +25 resistance to fire, ice, and lightning damage.

Tarth

Guerrilla fighters that like to hit and run. Like to combine slow and bows.

Challenge: Units attacked by this unit in melee have their movement reduced to 0.

Trapper: Allows unit to throw a net with 4 range that reduces and enemy's movement to 1 for 2 turns. 

Guerrilla: +1 move and + 2 initiative when below 50% health.

Krax

Defensive and dirty fighters.

Careful: +10 dodge versus ranged. 

Dirty Blow: A special attack that if it hits also reduces enemy accuracy by 10. 

Fallback: Unit gains +2 initiative for one turn when it is attacked while defending. 

Yithril

Strong and deadly melee.

Mighty: +5 chance to knock enemies prone.

Frenzy: Upon attack this unit gains +2 initiative for 2 turns.

Bulk: +2 hp and +10 weight capacity. -5 to dodge and accuracy.

Magnar

Flexible and dangerous warriors.

Spikes: Units attacking this unit take 1 damage multiplied by troop size.

Flame Tongue: Allows unit to breath fire to do (2 * unit size) +1 per level fire damage, with a range and cooldown of 4.

Dreaded: Units that attack this unit get -2 initiative for 1 turn.

Rosoln

Vampiric and unholy.

The current race bonus is way to weak and should be changed to 10-20% health drain on attack.

Unlife: Once per combat when reduced to 0 health instead of dying the unit is set to 50% health and knocked prone for 3 turns.

Ghoul: Upon killing a unit they gain +1 health permanently.

Death Touch: Units attacked by this unit loose regeneration and cannot be healed.

Umber

They like to swarm enemies with lots of weak units.

Mob: Every attack reduces enemy armor by 3 for 1 turn.

Savage: +2 attack -10 weight capacity.

Swarm: +5 dodge for every adjacent units.

Capitar

I can't really think of anything...