Apparently, there was some vague notion back in the day that DC's Secret Origins would run the origin stories of Golden Age heroes more or less sorta kinda in nearly the chronological order of their first appearances. Which, in turn, seemed to have created a groundswell of questions:
Note the claim that, at this point (1988), DC only had the right to the Marvel Family from Fawcett? That's interesting, because in the 70s DC certainly used Ibis, Bulletman, et al; and they used those characters a lot in the 90s in Power Of Shazam and Starman, and on in to the 2000s. Did they lose the rights for a few years? Did DC never properly have the rights to Ibis et al when they were used in the 70s? Or was Roy mistaken/misinformed?
Anyway, here's the list of most of the Golden Age heroes DC controls, and the order in which they first appeared. Enjoy this astonishing feat of pre-internet research!
Now that DC allegedly cares about "legacy" again, let's just wait and see how long it is until any of these folks appear in a Rebirth era comic, shall we?
From Secret Origins #23 (1988)