While we're on the subject of Norman Rockwell, please allow me an observation I've made about him as a character designer.
There are many who would quite incorrectly dismiss Rockwell as an artist enslaved by the photograph. The contrary is true. One of Rockwell's many gifts was his ability to choose what to use from a photo and what to throw out. More importantly, the photos he worked from were of subjects he posed and clothed himself. Now to my point: for a short but (I feel) illuminating lesson in character design, take a look at any Rockwell painting, and don't even bother with the faces. Look down. In every one of his paintings his figures are dressed in exactly the shoes that character should be wearing. Their color and patina, style and condition speak volumes about the wearer's history and personality. You almost don't have to look up again to know who's wearing them.
I am still not the costumer of characters I would like to be, not by a long shot, but artists like Rockwell make it very clear:
it's not the amount of details you choose to include,
but which ones.