It does make a lot of sense. I sorta like Godzilla as a GL, though. Willpower and imagination is Showa G all the way, man, and as I understand it, that's how the Green powers work. Is that right or not?
I agree on the Showa-era Godzilla diffidently, but the newer, less pleasant Godzillas wouldn't fit too well as GLs...although now thinking about it, Anguirus would make a fantastic Green Lantern!
I also find it humorous that DC Comics, historically, has way more giant monster creations than Marvel Comics do. But where as Marvel likes to re-use almost all of their characters often (obscure and otherwise), DC barley revisits anybody, unless they need a surprise 'D-List body count'.
Shame too, because more giant monsters as Lanterns would be nice...I know we have Mogu the Living Planet, but where was Giganta and Validus during the "Blackest Night" story arch?