Plaid Wool Jacket, Polka Dot Scarf (This is most probably too preppy for John, but I could see elements of it working for him. The vest and scarf and instead of the blazer take that pattern and put it on the pants.
Full marks to the blazer that is chosen to go with the boy-next-door outfit . "Blazers can be super casual. Just be sure to keep it simple with the graphic tee and other pieces so you don't end up looking like you are out of an episode of Jersey Shore.