Ehhh, all but the Accurate ki focus have two properties, like Mighty includes both Unerring and Empowered Crit. But unlike other superior implements, you can only use one property per feat, not one variety of ki focus. It strikes me as odd that ki focuses would be different from other implements that way. I love ki focuses, but I can't say I think they're in need of a nerf like that. Like, if you spend a feat on crystal orb, you get Energized (Psychic) and Undeniable, but spending a feat on inexorable ki focus gets you Energized (Force) or Unstoppable.