My army has about 70 Nord infantry, 5 archers, and 20 cavlary (including Companions). In battle, I usually find a hilltop or a tree, hold that position, and then wait for the enemy to come to me. Let's say I'm fighting Rhodoks...
If I order my cavalry to charge before my infantry meets theirs, then the enemy battle line will break a little, and it stops their crossbowmen from firing, but my cavalry just get crushed by the mob.
If I order my cavalry to charge after my infantry meets theirs, then they just ride their horses up to the melee and try to fight alongside my infantry. But their horses get in the way, they don't have the right weapons or armor for melee fighting, and they're just too expensive.
I've also tried ordering my cavalry to follow me while I ride circles around the enemy, but they inevitably drift into the melee and die.
It seems like cavalry are only good for mopping up the runners (assuming they didn't lose their horses or die during the main battle). Am I missing something here? I'd like to use a more complicated strategy, but nothing seems as effective as the Nord Steamroller.