Greg responds...

Let me handle your questions in reverse order.

When Alan Moore first suggested Watchmen, he was indeed planning to use the Charlton Characters. My memory is hazy, but I think it broke down as follows...

Dr. Manhattan = Captain Atom
Rorshach = The Question
Night Owl = Blue Beetle
Comedian = Peacemaker
Ozymandias = Peter Cannon?
Silk Spectre? = Nightshade?

Dick Giordano, who was executive editor at the time, was fond of the Charlton characters (having worked at Charlton way back when) and didn't want Alan to decimate the line-up that he had worked to get DC to acquire. He suggested that Alan create new heroes for the story, and I think everything turned out for the best.

Meanwhile, DC was reinventing all those old Charlton characters, and the job to revamp Captain Atom fell to Cary Bates and Pat Broderick. Cary brought me in to help.

As for other comics I worked on, well, there were many entries in Who's Who. Many letter columns for Tales of the Teen Titans, JLA and others. An issue of DC Challenge that I ghosted (the only time I've ever ghosted). Some Secret Origins stuff. And a bunch of stories that never got published. My one and only consistent comics writing gig was Captain Atom.