Based on what I see in the pictures, he looks okay to me! Have you consulted your vet about his body condition? If the vet says he's good, that may just give you peace of mind.
I'm of the opinion that it's better to keep growing dogs a little on the lean side (and even as they continue to age) in order to stress joints less. Seeing ribs on an inhale is not unusual, and some of that can change along with the lighting you're in, as well as other factors.
Some body condition scoring can definitely depend on the individual dog's characteristics (conformation, muscling, coat, color, etc). How you describe the fat covering over his ribs, he sounds like he's in a good place. Especially since you're making the effort to palpate through the fat, and not just going by "fur feel."
Dover von Ziegeln Zage (GSD, 3 yrs)
Dutchess Lena of Black Lake RATI (Keeshond, 12 yrs)
“Once you have had a wonderful dog, a life without one, is a life diminished.”