Some interesting ideas and yes, the faction differentiations are quite limited. The starter faction bonuses in particular lack depth and richness.
- Vlandia bonus: 20% more upgrade XP to troops from battles.
- Sturgia bonus: 20% less speed penalty from snow.
- Empire bonus: 20% construction speed bonus to town projects, wall repairs, and siege engines.
- Aserai bonus: Caravans are 30% cheaper to build. 10% less trade penalty.
- Khuzait bonus: 10% extra speed bonus for horsemen on campaign map.
- Battania bonus: Forests give 10% less speed penalty to parties.
I mean pfft. Surely some expansion of these would add flavour, replayability and actually prevent snowballing. Remove pure buffs and add some penalties too. Just to pull something out my ass for illustrative purposes-
Vlandia cultural traits:
Sweat on the training field: 20% more upgrade XP to troops from battles (Vlandian troops only)
Sword brothers: Companions gain XP bonuses.
Castle builders: Castle walls are tougher for the owner.
Sturgia cultural traits:
Cold lands breed hot war: 20% less speed penalty from snow. Only functions if party is at least 75% Sturgian troops.
Axemen of the north: Axe-armed sturgian troops have a small chance (5%) to destroy an opposing shield in a single strike.
Empire cultural traits:
Imperial knowhow: 20% construction speed bonus to town projects, wall repairs, and siege engines.
Imperial pride: Parties consisting solely of empire troops gain small morale and XP bonuses. Empire companions also.
Aseria cultural traits:
Sand and gold: Caravans are 30% cheaper to build. 10% less trade penalty. Caravans have additional guards.
Desert strike: Aserai cavalry gain speed and attack bonuses in desert maps.
Khuzait cultural traits:
Under our hooves: 20% extra speed bonus for horsemen on campaign map. Only functions when party is at least 75% mounted troops.
Meritocratic command: Stats improve faster through battle experiance.
Battania cultural traits:
Waystalker: Forests give 15% less speed penalty to parties. Easier to spot forest bandit lairs, and bonuses to attacking them.
Not one of us: If party is less than 75% Battanian troops, recieve a morale penalty. If more, recieve a morale buff.
The trees have eyes: When attacking in forest, chance for party to gain 'surprise attack' stat bonuses and enemy debuffs.
Or something.