While I was on vacation a hefty Unearthed Arcana article dropped with playtest material that either enhances or replaces existing class features. Let's take a look at the options and see what they do, if they work, or if they might need a further iteration. Because this UA article is long, I'm splitting it up into sections; this time we're covering the fighter, monk, and paladin. The bard, barbarian, cleric, and druid were covered here.
Superior Technique Fighting Style
You learn one maneuver of your choice from among those available to the Battle Master archetype. If a maneuver you use requires your
target to make a saving throw to resist the maneuver’s effects, the saving throw DC equals 8 + your proficiency bonus + your Strength or Dexterity modifier (your choice). You gain one superiority die, which is a d6 (this die is added to any superiority dice you have from another source). This die is used to
fuel your maneuvers. A superiority die is expended when you use it. You regain your expended superiority dice when you finish a
short or long rest.
Commentary. This Fighting Style option feels pretty weak. I think I would always take a "always on" Fighting Style over this "once a rest I can do a cool trick" one.
Other Style Options (note these are also available to paladins and rangers)
Being unable to see a creature doesn’t impose disadvantage on your attack rolls against it, provided the creature isn’t hidden from you.
Commentary. Being blinded comes up so infrequently that I can't imagine taking this Fighting Style.
When a creature you can see hits a target that is within 5 feet of you with an attack, you can use your reaction to reduce the damage the target takes by 1d10 + your proficiency bonus (to a minimum of 0 damage). You must be wielding a shield or a simple or martial weapon to use this reaction.
Commentary. I think this would be incredibly strong in early levels (essentially negating part of the opposition's action economy), but really lackluster at higher levels.
Thrown Weapon Fighting
You can draw a weapon that has the thrown property as part of the attack you make with the weapon. In addition, when you hit with a ranged attack using a thrown weapon, you gain a +1 bonus to
the damage roll.
Commentary. I like this, but I think it could also be stronger. I don't think a +1 to hit or a range boost on top of the rest of the feature would be out of order. I'm sure this is partially because I'm not much fussed about policing who can draw what weapon when, but I'd rather just apply the Archery fighting style to thrown weapons.
Your unarmed strikes can deal bludgeoning damage equal to 1d6 + your Strength modifier. If you strike with two free hands, the d6 becomes a d8. When you successfully start a grapple, you can
deal 1d4 bludgeoning damage to the grappled creature. Until the grapple ends, you can also deal this damage to the creature whenever you hit it with a melee attack.
Commentary. I really want to like this, but I don't think it makes unarmed fighting a competitive option. Giving up using a shield or a great weapon for 1d8 damage doesn't feel like a good trade. The problem is that making the damage any higher potentially steps on one of the monk's core features. It also suffers from a lack of ways to make unarmed damage magical to bypass resistance to nonmagical bludgeoning damage. I think what "brawler" characters need is a subclass, not a fighting style.
1st-level feature (enhances Maneuvers)
If you know any maneuvers from the fighter’s Battle Master archetype, you can replace one maneuver you know with a different maneuver whenever you finish a long rest. This change reflects your physical and mental preparation for the day ahead.
Commentary. Another enhancement that allows you to swap-out a feature that hasn't been working out.
1st-level feature (enhances Maneuvers)
If you have access to maneuvers, the following maneuvers are added to the list of options available to you. Maneuvers are available to Battle Masters and to characters who have the
Superior Technique fighting style or the Martial Adept feat.
Commentary. Okay, I'm not cut-and-pasting them all, but here are my general thoughts: Ambush, Silver Tongue, and Studious Eye all give you a non-combat option for your fighter, which is very cool. Since you get a limited pool of Maneuvers, you'll probably only take one of these at most, but they're nice ways to add flavor. Brace gives you an attack against anybody who gets up in your face for a superiority die, which is cool, but I wonder if that steps on the Sentinel feat a bit. Restraining Strike gives you a way to grapple and restrain, which is what many people seem to want out of the grappling rules anyway. Snipe gives you a ranged attack for a superiority die as a bonus action; that one seems very nice.
1st-level monk feature (enhances Martial Arts)
You can use this feature to define your monk weapons, rather than using the definition in Martial Arts. You practice your martial arts with specially chosen weapons, which become monk weapons
for you. You can choose a number of weapons to be your monk weapons equal to 5 + your Wisdom modifier (minimum of five weapons). The chosen weapons must each meet the following criteria: The weapon must be a simple or martial weapon. You must be proficient with the weapon. The weapon must lack these properties: heavy, special, or two-handed.
Commentary. I don't really get what this enhancement is addressing. It's nice to be able to choose your monk weapons, but since you can only choose weapons you are already proficient in I think this only lets you count weapons as monk weapons if you get proficiency in them from another source, such as a racial trait, a feat, or multiclassing.
2nd-level monk feature (enhances Ki)
If you spend 1 ki or more as part of your action on your turn, you can then immediately make one unarmed strike as a bonus action.
Commentary. This has to be a stealth buff to the Way of Four Elements Monk. Letting them have an unarmed strike when they burn ki on an elemental power is nice, but it doesn't really fix how few powers monks get from that subclass or the wonky way those powers are priced in terms of ki points. At least it's something. Funny thing about this one: I don't think it actually helps you at the level it becomes available.
2nd-level monk feature (enhances Ki)
When you gain the Ki feature at 2nd level, you get access to the following features.
Commentary. Distant Eye negates disadvantage on ranged attacks at extreme range, but how often does a monk make that kind of attack? Quickened Healing gives very few hit points in return for 2 ki points; that doesn't seem worth it.
Blessed Warrior (Fighting Style)
You learn two cantrips of your choice from the cleric spell list. They count as paladin spells for you, and Charisma is your spellcasting ability for them. Whenever you gain a level in this class, you can replace one of these cantrips with another cantrip from the cleric spell list.
Commentary. Do clerics really have any cantrips that a paladin would be willing to trade Great Weapon Fighting for? I guess it kinda gives them a ranged option aside from thrown weapons.
Note that rangers get a similar Fighting Style option with regards to druid cantrips, but shillelagh is an interesting spell for a ranger who wants to emphasize Wisdom over Dexterity or Strength. Both of these are okay, but I don't really see them becoming popular choices.