In the comics, Trixie has been working hard to change from that, and also ended up forming a bond with Babs because of it. Also, the whole "enslaved ponyville" wasn't totally her fault, as she was being influenced by a cursed magical artifact...and the fact her first visit, she was treated like crap, just because she used a story to try to keep a crowd...and no one bothered to blame the town idiots for causing the issue in the first place. And should Trixie be punished? Since Luna was never punished for allowing herself to become Nightmare Moon, and trying to kill her sister in order to dominate Equestria...than no.