Yeah, the availability IS a problem; I'm working through it for the first time myself. They didn't start releasing the full collections until a year and a half or so back, and they're still only available as 4 hardbacks for a rather bruising $50 each. (My comic shop holds occasional 25% off sales; I grabbed the first two up on such occasions.) But if you can afford $50 for a comic book, that's the way to go. (That or the $50 hardback collections of Palomar and Las Locas.) I assume there'll be paperback editions someday, but no word on that.
Can't fault the DCAU's take on the story; it was great. I'm surprised by how dark the last season of Superman got, and it sure ended on a downer.
Can't vouch for the Orion series from a few years back as I haven't read that; as for the current Death of the New Gods, I made it through #1 and then didn't buy #2. Embarrassingly derivative.
Did you read Seven Soldiers? There were Kirby/Fourth World tie-ins throughout, but Mister Miracle was the biggest, for obvious reasons. It recast the New Gods as homeless people on the streets of New York. Pretty cool, actually, precisely BECAUSE it was so much different from a typical New Gods story.
Seven Soldiers also follows Fourth World stylistically, in its method of storytelling, by rotating between different narratives that combine to form a larger gestalt.
How Morrison will do with a more traditional take is anybody's guess, but I'll vouch for his work on Batman. It's not as dark as Batman's generally been for the past couple of decades, but it's not as whimsical as All-Star Superman, either. (The whimsy is mostly to be found in Morrison's selection of reference material, rather than the narrative itself.)
Anyway. I'll at least give #1 a look.
