You can do stuff to weaken the Grove prior to going to the goblins camp... i.e. rat out Kagha as a shadow druid. That leads to a smaller fight that will reduce the number of druids you have to fight. Other than that, like has already been suggested, I would make sure you have a tank like Lae'zel in the party and kite them around. If you are playing a "good guy" then the easiest way to win is to just assassinate the goblin leaders. I would make sure you finish any side quests while you are there before killing the Hob as you will trigger the whole camp when you kill him.
