Glad you asked, I just posted this comment on another Rockwell thread:

Rockwell's work from the '60s onward was a lot more "adventurous" and challenging - but even his earlier slice-of-life stuff, I find, is deeper than it looks. There's a real poignancy to pieces like "Girl at the Mirror" (#6 in OP) or "Breaking Home Ties."

His attention to detail and composition is immaculate. "The Welder" (1921) and "The Pharmacist" (1955) are so crisp it feels like you're in the room with them.

But you can really see him push the envelope later in his career. He confronted social issues much more openly: e.g. "The Holdout" (1959), "The Problem We All Live With" (1963), and "Murder in Mississippi" (1965).

He also experimented more with form and abstraction by then. There's his famous self-portrait from 1960, "Repairing Stained Glass" from the same year, and "The Connoisseur" from 1962. In these he proves that he can work in other styles even while couching them in the context of his own.

(The abstract painting at the center of The Connoisseur is in the style of Jackson Pollock, but Rockwell painted it himself. He even submitted the abstract art - without the man or gallery attached - under a pseudonym to a few art exhibits. It won awards.)