The only reason WB is attempting Watchmen is because Snyder came onto the project and he got cred with the execs after Dawn of the Dead and 300.
Harry Potter is just one series of books. DC Universe is a series of hundreds of books and characters. Also it was an easy property to attract so much interest at the time.
Yeah, so? Does it make Watchmen any less ambitious and gutsy? An R-rated, complex, superhero deconstruction that some think will be impossible to pull off satisfactorly to the fans isn't rolling the dice? Dismissing the ambition and risk of that project because of past success is like dismissing Iron Man 2 because Iron Man was a success.
I'm sure there's a WB exec rolling his eyes at the idea that Harry Potter, with a very accelerated schedule, relying on child actors with no real box office stars attached, and with an ending that hadn't been written yet, was easy and unambitious to pull off. Or the idea that a company that wants to make 6 movies in 4 years is somehow more ambitious than a company that makes 6 movies every 4 months.
It's very easy to suggest that success was a no brainer with hindsight, but if it was so obvious back then J.K. Rowling would be a lot richer than she already is. We've seen plenty of franchises burn out after a successful first or second outing or fail outright, The Golden Compass, that I think it's a mistake to just dismiss how much work, effort, and ambition goes into sustaining a project this long. How ambitious and risky was the 2-shot of Flags of Our Fathers and Letters From Iwo Jima to pull off?
It's great that Marvel Studios has had one huge success and, at the very least, looks like they're going to make money with their second movie. And that they have plans. But, I think it's a mistake to dismiss another company because their priorities are on things other than superheroes, even though they make those too and other non-superhero comic book properties, as unambitious or lacking in plans.