While renaming SLS Las Vegas -- and we assume your suggestion would stretch to extending the idea with some "theming" -- as "the Stardust" might conceivably help that struggling resort by cashing in on the latter's considerable nostalgia value, our gut feeling is that any such move would likely do more harm than good. Fans of the 'Dust are extremely loyal to the original property and would probably deeply resent any such move by some upstart "pretender." As you mention, its location has been among several problems for SLS, none of which has been to do with its branding, which is (or was) probably one of the few things that counted in its favor. While MGM Grand managed successfully to transfer its brand to an entirely new venue post-fire, the attempt to revive the Aladdin (which had never been a success in the first place) proved to be disastrous.
Either way, it's something that almost certainly will never happen, due to the fact that Boyd Gaming still owns and controls the Stardust brand. As a previous Question of the Day (5/2/13) explained, "Usually, when a company is acquired, all trademarks are considered assets of the purchaser. When an individual property is sold (e.g., Frontier, Castaways, Dunes, etc.), it's usually a real estate transaction and the trademark may be held separately. There isn't a consistent rule and it often is buried in the sale documents."
In the case of the Stardust, Boyd valued the name and its cachet too highly to let someone else have it. The company already leverages the positive associations that the Stardust name conjures up at a couple of its other casinos: On the top floor of The Orleans is a party suite named the Stardust Suite. Also, at Boyd’s Blue Chip riverboat in Michigan City, Indiana, the event center is called the Stardust Event Center. And in one instance that springs to mind, back in April 2011, Boyd Gaming sued an Austrian-based online-gambling site over misuse of its Stardust brand name, filing a trademark-infringement complaint in the U.S. District Court for Nevada against the owner of stardustgaming.com and stardustgaming.net.
"It's an iconic brand. It's a matter of finding the right fit for it," says company spokesman David Strow, who adds that Boyd has no plans to re-brand any existing casinos with the Stardust name. Hence, for the foreseeable future, Vegas visitors wanting a fix of the Stardust glory days will have to console themselves with a tour of the Neon Museum (available by day or by night), where the last Stardust marquee (but not the original signage) reposes. You'll get a crash course on the glorious history of signage in Las Vegas and it's well worth the price of admission.