After finally managing to provoke those mages without getting the Thug achievement, it seems to make little difference to how the NPCs perceive you. Back at the Abbey for instance, typical responses still range from "Not interested" to "I don't want any trouble", and that's without assaulting someone. On my initial playthrough I played a half-Aeterna so I perceived these negativities as thinly-veiled racism aimed at my character, but now having played as all three races, it seems that there really is very little difference.
It would appear that it is personality that counts. I would imagine that if my character had a high personality level, she would be better liked regardless of race or Thug achievement.