Also chiming in with my fellow SAMs. Kaiten should remain! Not only is it an engaging mechanic, making sure you have the correct amount of Kenki to use it at the correct time but thematically wise it's also great, using that "power up" ability before you unleash Iaijutsu or Ogi.

The crit changes whilst at a glance, look good, it overall ruins are synergy with any other class providing crit buffs.

Overall it's a bad change and I hope SE realize that sooner rather then later.