[Crazy Jetty]

Actually, you *are* talking about alternate realities. All those examples are some of the best examples of alternate realities I can think of.
But it's more or less just arguing terminology. It's the all the same thing.

So on that note, I'd suggest:
Justice League: New Frontier- An alternate reality take on the formation of the Justice League. Set in the silver age, but with more modern story telling styles.

I would also suggest expanding your horizons to Self Contained stories. Stories that are "canon," and set in the mainstream universes, but really require nothing else to read them.
Batman: Hush- There's a new serial killer in town, and all the clues to his identity points to Jason Todd, the second Robin. Only he died in Batman's arms years before.
Identity Crisis- Someone is killing the loved ones of the various superheroes. Someone knows who they are. One of the best written stories of all time, IMO. And pretty damned heartwrenching in places.