Well, If you're a NE, there's always the shadowmeld option. In my experience it's best not to open on hunters unless there's no other target (or if its a last ditch effort to make a play objectively). Honestly the best way imo to take care of a hunter is to LOS, get some distance from the hunter, kill his pet then for a clutch restealth and GTFO. Usually by the time it takes for the hunters pet to be revived and get back to your location, you're out of combat and can get that restealth. Not many options in mid-field though. Unless you have a healer or another dps with you to back you up... you're in a sticky situation my friend.