Enough questions like that... this way lies madness. But I agree with you; A-SS and the JSA were pretty roughly treated. And I missed the Superfriends* from Earth-2.... I thought the occasional appearances were tantalizing and fun.

*Of course, they weren't CALLED the Superfriends... but it was emphasized that Superman, Batman and Robin, Wonder Woman, and Aquaman were removed from that past. I don't recall how Green Arrow and Speedy were treated, but the Seven Solders probably got pretty fouled up too.

*****

What's confusing to me now is that the pre-Crisis DC Universe was not confusing to me then. 

Probably 85% of what I read as a kid was Marvel, but if I picked up the occasional DC book that referenced the multiverse (like JLA/JSA crossovers), I didn't have any trouble following what was going on, and neither did anybody I knew. If anything, the parallel-universe aspect of those stories didn't detract from the fun; it added to the fun. It may have helped that my friends and I were all Trekkies who loved "Mirror, Mirror."

Maybe there were readers out there who found the whole thing baffling or off-putting; I've just never thought that the "confusing the readers" argument for Crisis held much water.

Air Wave

The Guardian

Captain Comet

Zatara (father of Zatanna, after all)

Immortal Man

Robotman (Robert Crane)

Manhunter (Paul Kirk)

Plastic Man

Wildcat

So much for Kal-El being Earth-One's first superhero, as was repeatedly stated before 1986. 

Adam Schulman, why is this a boxed set that fans should not buy?  Because doing so would... what?

Your list is excellent, and "Superboy/man was Earth-1's first super hero" is a tough nut to encompass. Then again, it depends on other factors. Superboy stories started before the Golden Age ended (Jan 45 for the Boy of Steel, and All-Star Comics featuring the JSA was published in Mar 51.) So the immediate question is - was there a Golden Age Superboy? 

You can get into a lot of fist fights (figurative, y'know) on when exactly the Silver Age started. Showcase #4? Superman #76? Detective #225? Strange Adventures #9? It's tough to set a timeline, let alone when Superman "debuted" on Earth-1.

And your list is excellent. Superboy met a number of super heroes. I think about "The Adventures of Superboy", "Superboy", and Justice League of America #144. Now we start playing with relative ages, but in addition to the heroes you listed, we COULD consider....

The Blackhawks

The Challengers of the Unknown

Congo Bill/Congorilla

Dr. Mist

Green Lanterns - Tomar-Re knew of Krypton's explosion and tried to stop it. Although not as permanently on Earth as Hal Jordan, he was active. Of course, we could throw in the Guardians of the Universe too.

J'onn J'onzz - it seems as if he's old enough to have been active on Earth prior to Superboy's first appearance

Rising Sun - actually, he appeared as an adult in a Superboy story so he's pretty likely.

The Seraph

The Spectre - he seemed to be on any Earth as necessary. But, y'know, God's will and all that.

There were also war heroes (Revolutionary, and WWs 1 and 2) that had their share of "super" heroes. 

Not a lick of these had interrupted continuity, and you're quite correct about the ambiguity of some of them - for example, it's perfectly obvious that Bob Crane was on both Earths. Mind you, there's nothing to say that this WASN'T the same situation as Superman, Batman and Robin, Wonder Woman, etc. - there were simply two of them.

It might well be that the problem was the insistence that Superman was the first super hero on Earth. Heck, post-Crisis, an objective observer might say that Superman was just a knock-off of Dr. Fate, right down to the blue bodysuit.

None of this was ever brought up - not because it didn't occur, but because no one needed to know about it. As Mr. Byrne has often said... just don't ever mention it again. But that was a little too simple for a big crossover event (money-maker? I think it's hard to tell at this late date.)

It was at that point I realized "Oh no..."