It looks interesting, but it does pose a few questions for me.
- Why not just use a fighter? Many of their abilities have mechanics that make sense as Samurai abilities. While being Dex based is nice, I am not sure how character defining it is.
- The wisdom archery thing is quiet interesting. A ranged defender can cause some issues though. In some games DMs don't like defenders marking then running away and hiding. I would expect a lot of Samurai to specialise in stealth and multi-class to get the Cunning Sneak advantage. A guy in plate mail shooting somebody then running away from them is what this style lends itself too, but is not really conceptually sound.
- Why do many attacks specifically mark targets as their special ability, if the Samurai does that on every attack, hit or miss anyway?
- Why is the level 1 Daily that is ranged or melee using Dex for the ranged attack? Won't it be taken by bow guys who will have Wis as a main stat?
- Why can they wear platemail automatically? Fighters can't and Scale suits the normal concept of Samurai armor quiet well. (Yes I know they had some armor that was closer to plate, but it is not necessary to be dressed as a samurai).
- What are their disadvantages and advantages compared to a fighter?
- Can they use another classes feats or abilities? Are they a subclass?
P.S. Thanks for not making the Katana a super-powered-all-conquering weapon. I am so sick of seeing that in every homebrew Samurai/Ninja version.