I'd be okay with that honestly. It would add more flavor to using Vlandia as I guess they're supposed to be some sort of expeditionary proto-Normans and add more flavor/realism to empire if they got some light melee cav options.
It would add uniqueness to Vlandia but at the expense of reducing the variety in the rest of the game.
Right now 4/8 kingdoms in the game (three Empires and Vlandia) use crossbows, and 7/8 use bows, creating good variety in ranged weapons.
If Empire lost crossbowmen, then only 1/8 kingdoms would use crossbows, so you would not see them when not fighting in Vlandia... which is 88% of playtime! So the ranged units you fight with/against would be a lot more repetitive, and gameplay content would be underused.
IMO, trying to create flavour by giving one kingdom exclusive rights to one fighting style is misguided, because that means that content gets underused in the game as a whole. Flavour is
best done by giving kingdoms
more of a certain type of fighter than other factions. This way, you show a speciality without killing variety.
For example, Khuzait has a larger amount of ranged cavalry than everyone else, so this gives them flavour. But if we instead made them the
only faction who could use ranged cavalry, that would be bad for the variety in the game.
and add more flavor/realism to empire if they got some light melee cav options.
I agree with you that more flavour is needed, and that many factions play too similarly. But if you did that, you would make the problem worse, as Empire's T5 unit roster would become extremely similar to Vlandia's.
Empire - noble melee cav, light melee cav, ranged inf, shield inf, shock inf, ranged cav.
Vlandia - noble melee cav, light melee cav, ranged inf, shield inf, shock inf, pike inf.
So an army of Empire or Vlandian troops would feel almost identical to fight as or against!
If you want to increase the flavour of factions, check out this thread, where I made suggestions on how to maximise the variety and historical representation of the different factions.
My way of adding flavour to the Empire without making them too similar to other factions is to make them into the pike-focused faction, with a weakness of shock infantry. This would give them four major differences from Vlandia's troop tree,
and be consistent with their real life inspiration,
and increase variety/flavour,
and make pike bracing more useful in gameplay.
Even the Celtic/Celtiberian/Welsh-inspired Battanians have light cav and mounted skirmishers - which make sense - their progeny (Gauls, mostly) were excellent skirmishers and horsemen in their own right.
Info on this here
https://forums.taleworlds.com/index...-equipment-changes.450649/page-4#post-9791329 I agree with them having mounted skirmishers, but don't think lancer cavalry was a big enough part of Celtic warfare to justify two different cavalry branches. They should just have one javelin skirmisher cavalry branch who have a lance as a backup weapon.