I'm getting, like, unhealthy amounts of mad, clicking on that broken link.
I think so, based on the cinematic line. In your basic Tarzan/Wolverine/Hulk fight, the hero is fighting at a base level of ability (X) thumping minions and whatnot, then the big bad annoys them, and they fight harder (X+Y). In your basic samurai movie, the samurai is mowing down minions at a base level of ability (X), and then the big bad insults his honor or makes a big move that proves the samurai needs to go all out (or maybe the leaves on the trees start falling down--samurai movies can be a little random), and the samurai kicks into a higher gear (X+Y).
It is a good question of whether the fighter should have a (mechanically) barbarianesque subclass. D&D fighters haven't traditionally been really about the second gear (being more the automatic transmission then manual in my car-based analogy).
I think it should be clarified if the Piercing Arrow ability of the Arcane Archer does the bonus force damage to all targets in the line. If that's so, than should Bursting Arrow do 4d6 damage at level 18?
The Knight's abilities rely too much on having the grid, the idea that if someone move "even 1 foot" for their abilities means it could trigger an almost all cases since people in fights do shift around a bit all the time. They should probably use 5 feet or 1 square in the description.
The Sharpshooter doesn't really work well with weapons that can only be reloaded once per round.
The Samurai is a fighter who draws on an implacable fighting spirit to overcome enemies. A Samurai’s willpower is nearly unbreakable, and the enemies in a Samurai’s path have two choices: yield or die fighting.
I don't see that as an issue and could easily see spending your full movement to trigger a subclass ability being added into the game.
Look at the other fighter archetypes. 7th level is supposed to be a ribbon ability. All four of these new fighters are consistent with this.Noble Cavalry - Another ribbon ability at 7th level, should be moved to 3rd, but that would make 3rd level quite crowded...but crowded with ribbons so not so bad.