Know Your Enemy: A fighter's handbook

[Strill]

Extra Attacks? Sorry, but just using a Cantrip and/or spell or spell buffed attacks scales just as well or better for most other classes.

Like hell they do. Only Warlocks can claim that, and their spellcasting is highly restricted to compensate. Why don't you show us the calculations to prove that.

And unfortunately the Eldritch Knight can only make 1 attack + Cantrip per round, or 2+ attacks, but never both. A second Action Surge at 17th level is indeed useful. But it can only be used once per Short Rest, and is not as useful as a Sorcerer's Metamagic (which is essentially a spell only Action Surge that can be used multiple times per day) or various Conjured creatures (which multiply your action economy).

Probably because replacing just one attack with a cantrip would be overpowered. A Fighter's attack action usually does at least twice as much total damage as a caster's cantrip. You're basically asking that the Eldritch Knight get +50% damage.

The strength of the Eldritch Knight is when you pull out spells like Magic Weapon or Haste on top of your allies' buff spells, and then finish it with an Action Surge. Like I said before, the Fighter is the best buff target.

Put another way, what benefit does the Eldritch Knight Fighter 20 get that a Fighter 2/Full Caster 18 doesn't get?

A lot more at-will damage, is the most synergistic buff target in the game, and more health and health recovery.

Unfortunately, I think that the Fighter just falls behind starting at level 6ish+, and none of its subclasses options can fix it.

How?

Second, I admit that the Eldritch Knight gets some great spells. But it gets fewer of them then literally every other spellcaster in the book (other then the Arcane Trickster, which also sucks). And only having one or two 6th level or higher spells is indeed a big deal, because each one of them is basically an encounter winning effect.

Of course they have few spells. They have top-tier at-will damage, and bonus feats to do even better melee damage. I don't think you've actually calculated it out if you think other classes' cantrips can compare to a Fighter's damage. (Also the Arcane Trickster is fine too)