if you want more Moore-on-superheroes I would recommend
Miracleman - Sadly uncollected due to nightmare legal fuckmines but easily torrentable. More "hardcore" than Watchmen in its "serious" take but pretty memorable due to that. When Kid Miracleman fucks up London there is an emphasis on FUCKED UP.
KIMOTA!Supreme - Somehow Moore takes a third-tier Rob Liefeld Superman clone and turn it into a fantastic metanarrative on the comics history, using a variety of art and writing style he creates a rich 50-year history for the character that pays homage to all the great stories and eras of comics. The best Superman story ever written is Moore's "Whatever Happened to the Man of Tomorrow?" one-shot, but I prefer this to "All-Star Superman" as the ultimate "long form" Superman experience. It's just rich and textured and creative and FUN FUN FUN.
And if you want the ultimate Hollywood widescreen superhero experience get the first 12 issues of The Authority

1-4: Defeat a 100,000-strong army of superpowered clones
5-8: Repel a full-on invasion by an interdimensional Earth attempting to destroy our world

Sliding Albion

9-12: Kill God
Ellis left the series at that point as there was nothing left to accomplish.
