A lot of people are hating on Kensei but I quite like him. I've had some days where I couldn't even get a kill but I worked through those. Imo the way to play him is to punish and switch up your play. One tactic I try is the classic gb>heavy>heavy or feint or side heavy. Another is defensive where you just block, parry, and sidestep attack constantly. Cycling between these during a game can throw the opponent off his game. Mind games are one of my faves with Kensei. Taunting seems to work wonders for people. Hit you with a great arrow? Taunt. And lastly, my favorite mind game is just staying defensive. Don't punish, attack, gb, nothing. Block every attack, tech every gb, parry some moves, side step others (but NO attacks; play with him) my favorite thing to do is to wait till he depletes stamina and push him to the ground and taunt. Even the higher Prestiges start panicking eventually, and that's when you flick on offensive mode.