So what if the guy couldn't draw pretty girls (or pretty men, for that matter). Ditko was one the best, most innovative designer/draftsmen ever. And he really shined during Marvel's "Fin Fang Foom" period.
For me, Ditto did his best work during that period through his Marvel years as well as the Warren work. All peak Ditko. I wonder, though, whether a problem for him was the shrinking of the art boards. He did some interesting pencilling at Charlton, but never (to me) inked as well after that first run at Marvel -- which coincided with the art size being halved.