If you imagine a concept as a series of dials you can twist around to tune in to the idea you have in your mind, what are the starting positions?
Starting positions, I think the PHB sums it up:
'All of these heroes are fighters, perhaps the
most diverse class of characters in the worlds of Dungeons & Dragons. Questing knights, conquering overlords, royal champions, elite foot soldiers, hardened mercenaries, and bandit kings—as fighters, they all share an unparalleled mastery with weapons and armor, and a thorough knowledge of the skills of combat.'
and
'As you build your fighter, think about two related elements of your character’s background: Where did you get your combat training, and what set you apart from the mundane warriors around you? Were you particularly ruthless? Did you get extra help from a mentor, perhaps because of your exceptional dedication? What drove you to this training in the first place? A threat to your homeland, a thirst for revenge, or a need to prove yourself might all have been factors.'
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To me the 'quintessential fighter is all those things. The fighter is probably the least bland creation-wise. Dex Fighters, Grapplers, STR fighters, etc etc.... It has more possible starting positions compared to other classes. One doesn't have to be the 'holy-knight', the 'warlock-patron', the 'nature druid'
The concept is more open than other classes, perhaps this is where you are tripping up?