Four of the first five ingredients are fillers - corn, corn gluten meal, and soy go in your pups mouth and come right out the other end!
You really need to define what you consider a filler to be??? Apparently you believe corn and soy just transit the digestive system providing little if any nutritional value- except for gas. If so then you are wrong.

Shall we start with Corn?

Nutritional value of yellow corn

Shall we do the math per 100gms: Fat 5 gms, Carbohydrates 74 gms (mostly starch), Protein 5 gms. That accounts for 84 out of the 100 gms as being utiliizable.

The digestibility of the protein content of corn is approximately: 66.4% for the essential amino acids, 62.4% for non-essential aimno acids, and 64.0% for the total amino acid content of the corn protein(s).

One scientific study of the digestibility of corn protein

But clearly the value of corn is in the carbohydrates, where sugars are a part of this nutritional categoy. Corn is not an inert filler in foods.

I'm not here to defend any dog food that has no meat listed as the first ingredient. But I'm not going to assume the puppy chow is Purina until the original poster makes that claim.

BTW- the Canidae seems to have excellent ingredients per their order. My Propet Large Puppy has in order: Lamb meal, brewers rice, ground yellow corn, chicken, corn gluten meal, chicken fat (etc etc), ground wheat, dried beet pulp, chicken meal, dried egg product, natural flavors (whatever that is), fish meal, brewers dried yeast etc. The point there are some foods that have corn right up there as a main ingredient, and yet my 3 yr olds (as my prior dog of 10 yrs did) thrive on it.

What might be of value would be for the dog food makers to put in percentages for each ingredient. For example is the Propet 90% lamb meal (doubtful), and 10% everything else. Is the Canidae 10% Chicken meal, 9.9% Turkey meal, 9.8% brown rice, 9.79%white rice, with the remaining 4% and below for each. All we get to know is the order, but not the exact amount. It might be surprising.

The puppy is 9 weeks old and is a high energy breed, I doubt she's going to get too fat on puppy food not for quite some time at least.
And neither did I state a 9 week old puppy that is actively growing is likely to become fat. But once that puppy reaches 1 yr of age a change in volume diet may be needed. My prior dog which was 1/2 Lab lived up to her Lab reputation and at 1 yr on free choice was 90 lbs. She pigged out on her food. I quickly got her down with scheduled feedings to her ideal weight of 72-74 in the summer, and 80 in the winter. No, never had any arthritis problems. My current two I regulated the amount once they got to about 6 months of age and avoided all weight problems.

Also keep in mind that while vets are a wealth of information on the HEALTH of your pet, vets are NOT canine nutritionalists.
I wonder where one can find the courses and the colleges that offer a degree as a Canine Nutritionalist? I did come across some canine nutrition classes taught by Vets. Now getting a Vet to talk about dog food and nutrition without fast shufflling you out the door might be a trick. But a Vet DOES know food nutrition, else they would be at a loss in treating metabolic disease.