Also remember, ask Elmsdor: he's your man
My tip is:
Karen if equipped properly is one of the most powerful character in the game after Loren. Since she can both do melee and ranged well. And has many useful skills like focus target. I maxed Focus Target to III so you get 30% damage bonus with all your attack. I was playing as Saren Warrior mostly, but I could switch place with Karen when the battle was getting to tough in the frontline, so I could heal / rez everyone with Saren and then switch back in the front row
