Is he fat?

My cat Oscar is 1 1/2 years old. He is very active and healthy. A couple of family members commented on his "lion pouch" he has, that saggy belly skin that some cats get. They think he is getting too pudgy. He is a big cat as in his structure is bigger than most cats. When I weighed him in June he was 14 pounds and the vet said he looked good. I can feel his ribs pretty easily and from the top I can see a waist indentation. he does have saggy skin on his belly and between his front legs, kinda like a lion has. I am wondering if this is normal or if he really is getting too fat. I have seen fat cats and they are usually fat all over not just in certain spots.
He gets a measured amount of dry food, and can twice a day. I feed a mix of Blue wilderness and wellness complete health or basically I rotate a mix of grain in and grain free foods, so they get a variety of high end foods. I adjust amounts as the grain frees are really high in fat usually at 18-20%. i usually feed a 1/4 cup in the morning and 1/8 of a cup at night. Usually there is some left over. On the can he gets a variety of high end canned foods. I give him 1 1/5 ounces in the morning and evening and he usually won't finish the morning amount.
I don't think he is fat and the saggy stuff is just how he is built. Some cats have it and some don't. When I was a kid i had a really petite female that had a huge lion pouch but she was only 8 pounds and if anything, skinny.
Just checking to see opinions and making sure I am on track with his care. I worry about diabetes and stuff.