I've found 2:
Paragon:

That ability is completely and utterly useless, since you are never in earshot of your Allies that often. And you don't get much benefit. Would have worked better at 200% speed.
Ritualist:

Yes, that's right, a Spirit! It summons a snowman named Jack Frost. I believe he attacks more frequently, since he has no aftercast delay. But, you can only have 1 of each within a certain range (like all other spirits)
What are the Dervish/Assassin skills?