I actually used a PF archetype when playing the second playtest adventure. I was a Pahtra Rhythm mystic disciple of Meyel, and chose the clawdancer archetype. In character, she was a dancer so finding a way to attack with her claws in a dance fit. Mechanically, other than being action-starved juggling between mystic buffs and actually using clawdancer attacks, neither I nor any of my fellow players noticed anything that felt off.