Like I said.... I think WATCHMEN is a masterwork as is. I like the work of both Moore and Gibbons in it.

And if not Dave Gibbons, I think it would be equally good if not better if another artist had drawn it, such as Alan Davis, David Lloyd, or some other then-unknown artist who would have drawn in equal detail with a more decorative linestyle than Gibbons.
Gibbons' work is competent, but a bit comic-booky and lackluster. It gives WATCHMEN a unique look, and reminiscent of the late-1960's Charleton work on the characters WATCHMEN is adapted from. In this sense, Gibbons' art is arguably perfect for the series. Compatible with work of guys like Ditko and Boyette who drew the original Charleton versions.

But any artist who collaborated with Moore would have brought his own contribution to WATCHMEN, just as Gibbons did. I just wonder if WATCHMEN could have been even better if it had been drawn by the likes of a Wrightson, Kaluta, Neal Adams, Arthur Adams, John Bolton, Charles Vess, Jim Starlin, David Mazzuchelli, Michael Golden, Tim Conrad, Alan Davis, David Lloyd, or some other then-undiscovered talent.
That's not a sense I get when I look at SWAMP THING by Moore/Bissette/Tottleben, or MIRACLEMAN by Moore/Leach/Davis, or "Pictopia" by Moore/Simpson, or MR MONSTER by Moore/M.T.Gilbert.


In a parallel example, CONAN by Barry Windsor-Smith is arguably unthinkable in its origins by any other artist. But Smith was actually Marvel's second choice. They originally wanted to give the series to John Buscema, but Buscema wanted too much per page, so they gave it to Windsor-Smith because he was cheaper, and they didn't want to budget much for a series then seen by Marvel's leadership as a risky non-superhero book. Which unexpectedly turned out to be enormously successful. After which Smith left, and they gave the book to Buscema anyway.

If Bissette/Tottleben had drawn WATCHMEN, you'd say "How could you possibly imagine anyone else drawing WATCHMEN?!?"
And suggesting Gibbons could have drawn it would now be the blasphemy!