Every Starman showed up in Jack Knights series, albeit sometimes heavily edited to fit what was then in continuity. So the Starman of 1951 was Charles McNider (a.k.a. Dr. Mid-Nite) spoilers:end of spoilers instead of Bruce Wayne.
and then David Knight
I've mentioned elsewhere that I'd like to see the N52 Earth 2 drop out of the Orrery of Worlds and be replaced by a new Earth 2. The basis for this new Earth 2 would actually be Jack Knight's Starman series and the JSA series that spun out of it, building the rest of the universe to conform to what we see there.