Yeah... this is something I just thought about, since some one on the board commented on how every reboot seems to change and hit Superman harder than just about every other character DC has:
Why do we have to chose anyway?
Originally it was because DC didn't have a Multiverse any more, but instead a merged Earth - but that changed like, 10-15 years ago!
So, why can't DC just use Rebirth as an excuse to remodel their Multiverse, and give us Earth-0 (Post-Crisis redux - aka Rebirth) Earth-1 (bronze age), Earth-2 (Golden Age) and Earth-52 (new 52) all at the same time?
Yeah, it would get super-crowded with all Supermen on the same Earth, but that could just be an introductory story, and then all of the Earth's could have a one-shot establishing each of them, with their Superman as the point-of-view figure. And then, why not publish a book here and there, with all of them? It could be a new variation on "The Adventures of Superman" -title: where a new writer comes in and does their take on a particular version of Superman. And, you could have recurring guest-appearances of the Supermen in the main books as well! : )
I'll leave the idea of what the main ongoing Superman should be, out of it, because it's just the general idea that's up on the table here - why erase ANY of them? If DC is about Legacy, then the legacy of Superman shouldn't be washed away - that was the original idea of Earth-2, keeping these older versions around, even though the regular comics had changed.
It honestly seems like such a simple straight-forward idea that I'm quite perplexed as to why DC themselves can't grasp it...