Druhzinas dismount (for any battle) to Feudal Foot Knights, the best swordsmen available to the Nov/Russians. I recruit them strictly for this feature. 325 florins for a 60-man Elite sword unit. They are the hidden gem of the roster by far.

Armour level 5 seems too high to me for some reason. There is a threshold where the unit will not recover from fatigue in the desert, I always thought it was 3 for infantry and 4 for cav.