Yes, the AI can't use limited range weapons at all, they just freeze in place. But, if they bait you to come closer and then kill you, then it's not so bad.
Samurai armour? Why? They aren't samurai, they are more like ninjas. Just like the Assassins - they are pretty much the same thing, just a different level.
Because we ALREADY have ninjas, and the assassins are badass as fuck, while the warriors feel like the lotus warrior feels like the black lotus grunts stole the assassins clothes, put on kevlar and bought a better melee weapon, and forgot a firearm. It really feels kinda cheap, as its a reskin of a STRONGER enemy, and warriors really provide little value in a battle. Honestly this is a big issue I have with black lotus, they are really meh besides the footmen, witch, and assassin, as the melee weapons make for such an easy kill.
You also missed the point, that this guy stood around like a dingus and did nothing UNTIL I got close enough, and had I just lit him up with mp5 bullets, this death wouldn't of happened whatsoever.
Beyond that, warriors really just don't provide much challenge, short of the time listed (which was 100% preventable) I've never died from a warrior since they always prefer melee and knives. I could propose 2 solutions, 1, that they get a boost to overall tu's (faster) and possibly get kamikaze AI, or 2, that they get armor, and a new skin which isn't just a pallet swap.
honestly, I think even giving the black lotus grunts higher TU's would be good : they train daily right? I figure they would be swifter because of this, and this would make them slightly more formidable this way.
In short, warriors don't feel particularly formidable or special in any real sense, to the point I actually prioritize them LOWER than grunts on most occasions... but besides witches, assassins and footmen, lotus is still a slight joke. And giving both warriors and assassins the same texture honestly just seems lazy on your part : no offense.
Whole point of such an outfit is stealth, which they dont have, and so for charging head long, traditional Japanese / Chinese armor would be very fitting.
And either way, the knives locking them in place feels like an exploit, as you can ignore them entirely this way if you stay outside the range. Maybe for the meantime you should remove knives from them....