Two of the best cards from The Opera, Wing Two of One Night in Karazhan are Barnes, and Kindly Grandmother. Here is a Kolento Barnes Kindly Grandmother Hunter Deck that combines them both.
It plays out like a midrange hunter, with the best Barnes possibilities being Savannah Highmane, and Infested Wolf. Two cards with decent deathrattles that you can benefit from with just the 1/1 body.
There is going to be a lot of play testing with Barnes over the next few days, I will post all the high-level successful lists here.