Been having a mooch at creating some rules which I think could be interesting.
No points values as yet, and nowhere near complete, but it has the makings of the rules of the Knights.
Grail Knights become Unbreakable rather than ITP, but can still make and accept challenges (indeed, have to accept challenges to keep the Blessing), and still have magical attacks.
Questing Knights no longer have a "Questing Vow", but simply Knightly characters attached to the unit and the unit themselves share "The Grail Quest", which gives them a chance during battles to become Grail Knights, after killing characters or Large targets.
Knights Errant make use of the Berserk Charge (from Frenzy rules but only get the extra attack if they take the Errantry Banner), with modifiers to the Berserk Charge based on General/BSB/Damsels/Large Targets/Fear Causing nearby.
Knights Errant are still standard knights, but get the option of choosing a Virtue (including the ability to fight on foot.
Dukes and Paladins can take Magic Standards as a Magic Item, but they do not otherwise count as a Standard Bearer (to represent the pennants).
Coat d'Arms - Knights have a 6" Inspiring Presence as if they were a general. Generals have +6" Inspiring Presence.
Lance Formation - simplified to Devastating charge and allows supporting attacks up to +3. As Knights are now Monstrous Cavalry, it still allows for +3 wide, but also for larger units of Knights to horde.
Blessing of the Lady - 5+ Ward Save basic, or +1 to existing Ward Save. The save is lost if they refuse a challenge or flee. May be regained by highest Ld Knight in the unit having his challenge accepted (leading to an opponent making the choice of sacrificing his characters attacks or giving the Knights a Ward Save).
Breton Lance - +2 Strength and +2 Initiative in the first turn of combat. Knights Errant are I5 on the charge, Realm I6, Paladins and Grail Knights I7, and Dukes I8.
"I'm using this one" - for magic weapons, may choose to use Lance on the charge, or magic weapon. If Lance is used, and has a magic weapon, automatically swaps to Magic Weapon rather than Hand Weapon.
Breton Warhorse - as mentioned before, Monstrous Cavalry, +2 armour save rather than +1 (essentially barding without movement loss), and no longer subject to Fear from Flaming attacks.
Louen - absolute monster king character, meant to represent strongest king since Gilles. Can now be taken on horse, or on Beaquis. Has a 24-30" Inspiring Presence (essentially a 60" bubble when mounted on Beaquis), and all friendly models are stubborn. Could be a bit OTT, but I'm going to make him cost that much. If killed, friendlies have Hatred. He has a 4+ Ward rather than 5+ from the Blessing, and auto regains a wound at the start of his own turn. He must issue and accept challenges, and has two virtues - confidence and purity. Sword of Couronne gives +1 Strength, and enemies -1 to hit. Undead models in B2B must pass Initiative Test or suffer a wound. If targetted by a spell, must roll equal to or lower than the number of dice used to cast the spell on a D6 and its nullified. Beaquis has Multiple Wounds (D3), a 4+ Armour and a 5+ Ward.
Bhoemond - Dragonslayer, HKB, Lance ignores Scaly Skin, Morning Star has Multiple Wounds (2), 2+ Ward versus Flaming attacks, Destroys magic weapons if he passes armour save, and rolls a 4+.
Armand - BSB and General all in one. His unique standard autodisrupts and enemies lose Steadfast.
Reynard - grants a knight unit ambush, has 2 S4 attacks, and a special shooting attack, which targets enemy - enemy must pass I test, or suffer a S4 hit, if failed on a 6, S4 Multiple Wounds (D3).
Bertrand - Forest Striding Skirmishing archers, enemy musicians have no effect (meaning drawn combats are won in the event of archers). Can become stubborn in exchange for stupidity.
Tristran - Paladin Questing Knight, Bound spell to buff the questing knights.
Odo - Founder of the Border Princes, he and his unit hate all greenskins, undead and daemons. If he is general, all KotR and Errant benefit from it as well.
Virtues - can be taken by KotR, allowing for Dukes to join like units from their own Dukedoms. Mostly unchanged although the more powerful ones have lesser effects - Heroism and Knightly Temper become ItP or Hate enemies with shooting attacks while characters have the higher effect. Stoic BSB's have 18" range. Empathy allows units of Footknights to represent Montfort, Characters may choose to become "Peasant champions", giving them, despite being on foot a 24" Inspiring Presence if the General.
Magic Items - Conqerors Tapestry - essentially a War Banner, adds +1 for each standard captured, and doubles Victory Points.
Lore of the Lady of the lake - unfinished, but I have some favourites, including Toadfall (S1 rain, but enemy wizards must roll on miscast).