I don't know what constitutes a 4-star, 5-star, or 6-star. From just the stuff you posted above, this is a moderate food (carbs content is approximately 42%). Peas is high protein plant matter so with only a 24% protein content, it seems like the animal proteins from the salmon is not that much. So all the carbs and plant matter is probably why your dog is pooping a lot more.
So, at first glance, this is an okay food to feed your dog. But, there are better ones out there.