one thing I noticed - there was no collision detection for the horses (and for the humans either I think), are you planning on implementing a physical engine of some sort? (Ragdoll, Havoc - those are free I think..)
Would be way cool (even if it was LOD somehow so it doesn't clot the system) to see lines of enemies being split by charging cavalry with people flying around limbs waving wildly...(also it could add some dynamic to the fights, for instance the ramming/shield bashing move could cause some wilder interaction. It's probably because of the placeholder animations, but the combat looks a bit slow and dull at the moment.)
We're planning to use Steering Behaviors, we already implemented some algorithms (Flee, Pursue, Arrive) and we are working on Formations flocking, Push and Queue. The result will be a lot better than using classical AI with physics. And the final result will be exactly like you said: Horses splitting formations, narrow fighting, pushing, formations breaking and regrouping... formations will act naturally and as a real mass of people.
And about combat being slow and dull, that's mainly because we'll have to add lot of animations and attacks, and we need to improve AI to not stay static. But the combats are already AWESOME in First Person View. Immersion is total! We're making one of the most realistic FP view ever.
Thanks for your interesting