The story as it is could work as a PG-13 movie, given a few tweeks.
-The first major plot point is the fact that the wolf packs are suffering through a food shortage. We need to see one of the weaker pups wither and die from starvation, making Winston more desperate for a way to end the crisis.
-There could be some OTHER wolves who got captured along with Kate and Humphrey. Once they discover their reasons for being brought to Idaho, they take their roles as repopulators a LITTLE TOO SERIOUSLY, and Kate-Humph have to fight them off before she becomes an unwilling mother.
-Wolves are carnivores. No sense in dancing around the elephant in the room that these characters are all KILLERS. There's no need to go overboard on the gore factor, but the movie shouldn't be afraid to show them eating meat.
No she didn't, she gave him an unidentifiable cutlet that you might find as a free sample being offered at the grocery store. Let's see them eat REAL meat, like the zebra leg that Scar offered the hyenas. lol
Maybe more creativity, personality, and still avoiding some generic realism only like "wolves are wolves" for example because doing that example would ruin what made this movie good on it's own and probably turn this into a COMPLETELY FORGETTABLE movie. Worse than one of the sequels.
Many people like adding human personal features inside four legged animals because it adds more maybe.