He is the best at fighting already without those buffs. He just is not as far ahead.Not really no. I want a Goading attack features that trades the extra damage dice for repeatability.
Why the heck not? He's the FIGHTER, he should be the best at FIGHTING because that's all it seems to get. I'm really annoy at this weird attitude I see all the time that 'If the Fighter can do X, every Tom, Dick, and Harry who swings a sword should be able to do it too" as if the Fighter is some sort of default non-class you apply to anybody. No. The Fighter is a specialist in his own right and if it gets something unique then so be it. The Bard and Cleric get Spells, the Barbarian gets Rage and other abilities. The Fighter can Goad. Or Menace, or Distract or Push 5 feet (you could do it at-will in 4e and it didn't break anything!) on a hit.
With a fighter and a 20 strength you will be doing 2xweapon damage +10 at 6th level. Someone using a blade cantrip is doing 1xweapon+1d8+4. So they are a little bit behind - about 6 points or so depending on the weapon with the ability to occasionally manage the same by getting rider damage from the cantrip. The Cleric needs to invest in something to get there, either a Race, subclass or feat and he is still behind, just not far behind the BASE fighter. Give the fighter another 1d6 per turn for no reason, along with an effect like goading and then action surge and whatever he gets from his subclass on top of that and he is way, way ahead.
But it is even better and more fun for the table to limit it to once per short rest .... if you chose that fighting style and never get to use it at all if you don't. That keeps the fighter from overshadowing other characters in combat.Just limit the goading or whatever to once per turn if you think it would break the game.