Muslim and tribal nations are useless in multiplayer

[Surt]

Despite the recent slight nerf of the H. Cavalry there is no stopping the European knights from overrunning any army.

No Hattin is possible, or the later dying off of the various invading armies due to disease, impetuous charges of the nobles.

Some possible mitigations, all required:
if H. Cav is more than 20% nobles will recklessly charge : -2 dice, overflow +dice to opponent or minus to entire stack.
Disease and lack of water :Each time an European H. Cav or H. Inf enters arid/African or desert region costing 1 endurance and 1 health respectively, and same for starting in those.
Dutch / frisians used this against H. Cav/Inf: Add marsh and lowland to clumsy.

[Pocus]

Their spearmen were reinforced in the Advance Patch.
In the Companion Patch all western knights will have a specific Clumsy modifier also applying in arid terrains. Basically only open/clear and non-arid steppe will not give them a penalty.