I tried to update the AD&D fighting styles and expand them to a 3-level system like the Ranger fighting styles.
I then extended that to armor, shield, and a bunch of the existing feats, as well as doing the overhaul of specialization.
As an extra, a change to weapon finesse.
Rather than a Feat tax, this is altered to an Equipment tax, like composite bows and adding Strength to damage.
Weapon Finesse: Deleted. A light weapon or a one-handed weapon that can be used with Weapon Finesse may be purchased as an Agile Weapon. This costs 100 gp per point of Dexterity bonus that may be applied to the attack roll.
Armor StylesArmor and shields have a number of feats available to improve them. This simplifies a bunch of them.
Armor Proficiency: As per the PHB.
Armor Specialization (by armor type): Treat the armor as half its weight for the purposes of encumbrance.
Improved Armor Specialization (Light): Apply the armor bonus to touch attacks.
Improved Armor Specialization (Medium/Heavy): Treat the armor as light/medium for the purpose of speed. Reduce the ACP by 1.
Greater Armor Specialization (Heavy): Treat the armor as light for the purpose of speed. Gain DR 2/–.
Shield Proficiency: As per the PHB but includes Extreme Shield and Tower Shield.
Shield Specialization: Improve shield bonus by +1. Reduce flanking bonus by -1.
Improved Shield Specialization: Apply shield bonus to touch AC. Reduce ACP by 1. Reduce ASF by 5%. Reduce flanking bonus by -1
Greater Shield Specialization: Eliminate flanking bonus.
Note: All shields may be used to make shield slams.
As an extended variant, rather than armor "weights", AD&D divided armor by material - Leather, Chain, and Plate. I rather favor that myself, but used the core system here.
Weapon Fighting StylesThese are the basic weapon combinations as styles. The listed classes have "proficiency" with them. Other classes would need to spend a feat on proficiency first.
They are presented as feats. They could be added to Fighters, Paladins, Rangers, and Rogues as standard class features similar to how Rangers have them now.
They replace a number of base feats for feat chains, tying those feats directly to styles, and trying to smooth out the advancement.
(Clerics, Druids, Fighters, Paladins, Rangers)
Weapon and Shield Style Specialization: Retain AC bonus when using a shield as an off-hand weapon. Trade -2 BAB for +1 to shield bonus to AC, max +4 to shield bonus.
Improved Weapon and Shield Style Specialization: Reduce off-hand penalty to -2. Trade -1 BAB for +1 to shield bonus AC, max +6 to shield bonus.
Greater Weapon and Shield Style Specialization: Eliminate TWF fighting penalty. Apply shield bonus to touch attacks. Trade -1 BAB for +2 to shield bonus AC, max +8 to shield bonus.
(All classes)
One-Handed Weapon Style Specialization: Gain +2 dodge bonus when fighting with a weapon in one hand and the other hand empty. Trade -2 BAB for +1 dodge bonus AC, max +4 AC.
Improved One-Handed Weapon Style Specialization: Trade -1 BAB for +1 dodge bonus to AC, max +6 AC. Free parry or feint each round.
Greater One-Handed Weapon Style Specialization: Trade -1 BAB for +2 dodge bonus to AC, max +8 AC. Parry at will.
(Clerics, Druids, Fighter, Paladins, Rangers, Wizards)
Two-Handed Weapon Style Specialization: No initiative penalty for weapon. (A two-handed weapon normally applies a -4 penalty to initiative.) +1 damage when using a one-handed weapon with two hands. Trade -1 BAB and -1 AC for +1 damage, max +4 damage.
Improved Two-Handed Weapon Style Specialization: Trade -1 BAB for +1 damage, max +8 damage.
Greater Two-Handed Weapon Style Specialization: Trade -1 BAB for +2 damage, max +12 damage.
(Fighters, Paladins, Rangers, Rogues)
Two-Weapon Fighting Style Specialization: Reduce penalties to 0/-2.
Improved Two-Weapon Fighting Style Specialization: Use two one-handed weapons.
Greater Two-Weapon Fighting Style Specialization: Eliminate penalties for fighting with two weapons.
(Fighters, Paladins, Rangers, Rogues)
Archery Style Specialization: May single move and fire one less arrow. May full move and fire one arrow.
Archery Style Specialization: As per Shot on the Run and Precise Shot.
Archery Style Specialization: As per Improved Precise Shot.
(Fighters, Paladins, Rangers, Rogues)
Mounted Archery Style Specialization: As per Mounted Archery.
Improved Mounted Archery Style Specialization: As per Precise Shot.
Greater Mounted Style Specialization: As per Improved Precise Shot. As per Improved Mounted Archery.
(All classes)
Thrown Missile Style Specialization: May single move and fire one less arrow. May full move and fire one arrow.
Improved Thrown Missile Style Specialization: As per Shot on the Run and Precise Shot.
Greater Thrown Missile Style Specialization: As per Improved Precise Shot.
(All classes)
Unarmed Style Specialization: As per Improved Unarmed Strike and Snap Kick.
Improved Unarmed Style Specialization: As per Deflect Arrows and Stunning Fist.
Greater Unarmed Style Specialization: As per Extra Stunning, Superior Unarmed Strike, and Versatile Unarmed Strike.
Tactical Fighting StylesThese replace some of the additional effects of feats in Feat chains, combining multiple feats into higher levels of specialization.
Combat Expertise Style Specialization: As per Improved Disarm, Improved Feint, and Improved Trip.
Improved Combat Expertise Style Specialization: As per Snatch Weapon, Surprising Riposte, Knock-Down (with no required Strength).
Greater Combat Expertise Style Specialization: As per Allied Defense (requires Weapon and Shield Style or One-Handed Style Specialization to use), Deft Strike (with no required Sneak Attack), and feint as a swift action.
Dodge Style Specialization: As per Dodge but the bonus applies to all enemies and increases by +1 at 5th, 10th, 15th, and 20th level.
Improved Dodge Style Specialization: As per Mobility, Sidestep Charge (XPH), and Spring Attack.
Improved Dodge Style Specialization: As per Whirlwind Attack
Mounted Combat Style: As per Mounted Combat.
Improved Mounted Combat Style: As per Ride-By Attack and Trample.
Greater Mounted Combat Style: As per Mounted Mobility, Spirited Charge, and Cavalry Charge.
Power Attack Style: As per Improved Bull Rush, Improved Overrun, and Improved Sunder.
Improved Power Attack Style: As per Pushback and Resounding Blow.
Greater Power Attack Style: As per Combat Brute and Shock Trooper.
Weapon SpecializationThe revision for specialization. This is a Fighter "thing" - something special for just them. Other classes can take the reduced versions listed first, with Wizards getting hit with an extra Feat tax to remind them to cast spells and not try and try to out hack-and-slash the mundane murderhobos.
Martial Wizard (Wizards only: Requires BAB +1. Required for a wizard to take Weapon Focus.
Weapon Focus (Non-Fighters): Requires BAB +1. Gain a +1 to hit with a specific weapon.
Weapon Expertise (Rogue, Cleric, Arcane Caster): Requires BAB +5. Gain an iterative attack with a specific weapon.
Weapon Expertise (Ranger, Paladin): Requires BAB +10. Gain an additional iterative attack.
Weapon Specialization (Melee): Requires BAB +3. +1 to hit, +2 to damage. Gain an additional iterative attack.
Weapon Specialization (Missile): Requires BAB +3. +1 to hit at all ranges. +2 to damage at point blank range (30 ft. for bows, 60 ft. for crossbows). Gain an additional iterative attack.
Improved Weapon Specialization (Melee): Requires BAB +5. +3 to hit, +3 to damage.
Improved Weapon Specialization (Missile): Requires BAB +5. +2 to hit at all ranges. +3 to hit, +3 to damage at point-blank range.
Greater Weapon Specialization: Requires BAB +7. Improved Initiative, Improved Critical with weapon. Far Shot with missile weapons.
Supreme Weapon Specialization: Requires BAB +9. Additional iterative attack. Improved Weapon Attack (as per Improved Natural Attack but applying to a specific weapon).
I still need to contemplate turning Berserking into a style chain.