I can't help you with adjusting the settings (aside from the obvious damage setting in the options), but the low/non-existing damage can have several reasons.
1) Your base weapon damage is too low compared to their armour rating. Lords have pretty good armour in general, a few even wear a Coat of Plates, only weapons with piercing damage can deal a considerable blow against those.
EDIT: I just re-checked, there are two variants of the Flanged Mace, one has the damage type blunt and the other one is piercing. I guess you wield the latter with a base damage of 31. While that's not terribly much when facing heavily armoured guys, you should still be able to hurt them with that weapon for more than 3 points.
2) Your attack speed is too slow. Every attack gets an attack speed modifier. When trying to stab an enemy with a lance while both of you are standing still, you will most likely deal 0 damage every time. When on a horse and charging though, even the less powerful lances/spears can pack quite a punch. The same applies to the rest of the weapons, the more force you can put behind your weapon, the more damage it will do.
And lastly, yes lords are machines when it comes to speed, pretty much all of them have proficiencies between 300 and 400 with their weapons of choice, because of that they can attack/react lightning-fast. Try to get close and after blocking perform a kick, that puts them off-balance and gives you an opening to attack. After all they are meant to be the most powerful units in the game, neutering them into becoming pushovers will suck out the fun, trust me. And we already need every bit of fun to make this mod work.