Mark Millar deserves some credit for telling a story with a villain character who starts out troubled and conflicted but ends up becoming completely evil rather than some sort of reluctant anti-hero. Wanted clearly began life as a Secret Society of Super-Villains elseworlds story in which the son of Deadshot trains under Catwoman and Lex Luthor to take revenge on the Joker and his allies for assassinating Deadshot in a gang war on a world ruled by organized crime families of super-villains. The real fun of the book is trying to figure out what DC or Marvel character each villain is a thinly disguised version of.
I think a lot of the one star reviews come from people who actually enjoyed the book until the last page on which the main character verbally assaults his fanboy readers. If you are sensitive about your comic book vice you might want to skip the epilogue.