Watchmen was good, but it could have easily been great if more detail had been injected into the screenplay. However, I'm not referring to anything akin to a one-time, graphic novel masterpiece.
I'm talking main fictional entities which have been comic book company title staples for decades. In DC Comics case, I'm speaking of Superman, Batman and Wonder Woman--who are its top three characters (a.k.a. heavy hitters)--in addition to The Flash, Green Arrow, Black Canary, Martian Manhunter, Hawkman, The Atom, Captain Marvel, etc., etc.
The mythos established by DC Comics precedes that of Marvel Comics. Yet, it is Marvel which has made the more impressive book-to-movie/television transition.
If not for Saturday morning cartoon/direct-to-video offerings by DC over the past decade or so, the gap between the two companies would be even wider. And that's saying something considering some of the infantile material DC has endorsed.
For example, compare the Teen Titans series (DC), which Cartoon Network aired, with Wolverine & The X-Men (Marvel), which Nickeleon debuted. The former is comedy based and would insult even any child who has read the title (especially the issues printed during the 80's). The latter is dramatic with damn good art thrown in.
All-in-all, it's something which I've never understood about DC. Their movies and/or television series should be on-par with that of Marvel, if not surpassing Marvel's. They aren't and it's not even funny how wide the gap is between the two.