On the whole food issue, the food you're feeding now sounds fine.

However, if you want the most nutritionally dense food as possible, Innova Evo would probably be the way to go. Most kibbles offer 200-350 kcal/cup. Evo offers about 530 kcal/cup. That way, your pup literally doesn't have to eat as much.

(You can find Orijen in American stores, too, but it isn't as readily available as Evo )