Nope, from my experience Nova Launcher uses less battery than even the default TouchWiz Home. Not kidding, this is the first thing I change whenever I get a new phone.
Nova Free Version + Cubes Icon Pack, Background is parallax 3D. You can't tell but it moves when you move the phone. All the parallax wallpapers are very cool. Also my all time fav app "app dailer pro" i rarely go hunting through app drawer or contacts anymore.