I believe early neutering can result in a taller dog. Certainly it is true with horses. Geldings will generally end up taller than stallions, all other factors being equal. Genetics should be the determining factor, but lots of food early can result in faster growth, not necessarily a larger animal at maturity. OTOH, inadequate nutrition can stunt growth. Line breeding, overdone, can result in smaller animals, (I know someone who is turning a large breed into something approaching dwarfs because her stock is so inbred…..not on purpose, I should add), and outcrossing can buy you "hybrid vigour", where the offspring are larger than their parents.
I think the "perfect dog" is the one that suits you. Bonus if others also think he is perfect.