I can't say anything to positionals fitting a job's fantasy, because aside from a Ninja backstabbing a target, I've never once considered positionals as being part of the fantasy.

I will say though, that I strongly disagree that anyone benefits from their inclusion. Getting stuck with a dps who doesn't care about landing them hurts the entire party.

Also as just a personal opinion, Kaiten was boring, and Zanshin is an amazing new use of Kenki.