I think Fighters are in a good place, and I like all the subclasses in general.
I feel like the Eldritch Knight is much improved over its 2014 incarnation but is a bit behind the power curve in the middle levels. Thus I offer a slightly buffed version of War Bond and an optional feature swap out at level 10.
I personally enjoy the Slayer class from Pathfinder 1e, and miss such an option in D&D. There are of course ways to approximate the concept via Assassin Rogues, and so forth. However, I offer the Eliminator subclass for Fighters as another option.
Side note: yes I know that technically Slayers are supposedly a hybrid of Ranger and Rogue, but they lack spells so Fighter seems a better fit for them in 5e to me.
I offer the Esoteric Archer subclass, an alternative to the Arcane Archer from 2014's Xanathar's. The design intent of this subclass is to raise the floor and reduce the feat tax for a ranged martial for tier 1 and 2, then add some AoE / control / boss lock options starting at tier 2, and then build on both foundations through tier 3 and 4. The mystical Hawkeye / Green Arrow feel should be there -- they should be best in slot archers, with enough trick arrows to have big moments without stepping on the toes of spellcasters too much.
I personally enjoy the Cavalier class from back in the day, and from Pathfinder 1e. Simultaneously, I was frustrated by the Cavalier, Purple Dragon Knight / Banneret, and Samurai subclasses of 2014 D&D. So, I made a mash-up Knight subclass for Fighters as a replacement, with virtues and distinctions that can be mixed and matched to represent many different Knightly Orders or player preferences.
While Champions and Battle Masters are cool and all, I feel like 5e overlooks the fantasy of a rough and tumble scrappy survivor who knows how to handle themselves when things get violent. So, I offer the Roughneck to fill that niche. They've been around, learned enough to get by, are hard to kill, and when they have to fight they do it dirty.
I offer the Spellblade as a variant of the Eldritch Knight that uses spellbook style casting and focuses on storing spells into Melee weapons.