Druzhinniks shouldn't have their horses removed, but they should have their spears replaced with a long 2-handed weapon like an axe in my opinion. This way, they would be able to perform a unique function of "mounted shock troop", where they can use their mounts to move and reposition quickly and then dismount if the player wishes (and also be more effective in sieges).
I understand why people want the Sturgian noble troop to be a foot troop, as there are already 3 other noble mounted melee cav troops, but having a noble foot infantry unit would render 1 or more of their commoner foot troop trees useless. One change that would give diversity to noble troops would be to split Empire noble troops to 3 - one for each imperial faction:
- The Northern Empire noble troop would be the Vaegir Guard who would be a Varangian Guard inspired noble shock infantry with a 2H axe and a 1h or polearm with a shield (already exists in lore, which is a plus).
- Southern Empire would keep the Cataphracts, since they would be the geographically closest to the Calradian analogue of the Parthians, who inspired the Roman Cataphracts.
- Western Empire would be crossbows + sword & board infantry, inspired by the... umm... Ballistarii? Genoese? Precursors to the Rhodok military doctrine in lore maybe?