Let me make something clear up front: John Carpenter's The Thing is not a remake, at least not in my eyes. Christian Nyby's "original", The Thing From Another World, is a movie loosely based on John Campbell Jr's novella "Who Goes There?", changing just about everything but the basic plot of an alien being found in the ice in the Arctic - the alien's MO, the characters, etc are all the invention of that film. Carpenter's version tosses in a few nods to Nyby's (the way the on-screen title appears, for example) but otherwise went back to Campbell's original story and more or less presented it faithfully: the heroes, the blood test, the "dog-thing" - all of these iconic things are from the story and all but ignored by the other film. I may refer to it as a remake from time to time for simplicity's sake, but to me, it doesn't quite belong with the Halloween (2007) and Night of the Living Dead (1990)s of the world.
Basically it comes down to what the filmmakers of the "remake" are actually drawing from, primarily: the book, or the previous film. You just have to look at the many versions of Dracula and Frankenstein to see the difference - would you refer to the Hammer Dracula movies as "remakes" of the Universal ones from 20 years earlier? There's a reason why Kenneth Branagh's 1994 film is called Mary Shelley's Frankenstein, not "James Whale's Frankenstein" (or Terence Fisher's, or, hell, J. Searle Dawley's) - he's making it clear he's going back to the source. There are some exceptions of course; I don't mind using the word "remake" for Matt Reeves' Let Me In, because so much of his film was influenced by Tomas Alfredson's earlier Let The Right One In (particularly in the production design) while leaving out the same elements that Alfredson ignored from John Ajvide Lindqvist's source novel. Likewise, even though Psycho is based on a novel, there is no question that Gus Van Sant's version is a remake of Alfred Hitchcock's film.
That's why, to me, The Blob is the one that filmmakers should look to if they want advice on how to go about a true and pure horror remake, when there's nothing else to draw from but the original film. Released in 1958, The Blob was an original idea written by Kay Linaker (who coined "The Blob" - the original title was "The Molten Meteor") and Theodore Simonson, and was released as the B-picture to I Married a Monster from Outer Space, another "alien impersonates a human" story that has been largely forgotten over time. Realizing audiences were having more fun with The Blob, the distributor swapped the order and it became a surprise hit, grossing 4 million on a budget of $110k, while helping to launch the career of its star, a young man named Steve McQueen (billed as Steven), who was paid a mere $3,000 for this, his first starring role.
But it was also very much a product of its time, and unlike the humanoid aliens or rear-projected "giant" insects that terrorized audiences in the 1950s, the titular blob was a full-blown special effect that wasn't easy to effectively create with the FX limitations of the day. They're fine for what (and when) they are, but it wouldn't be until the '80s that makeup and FX teams could fully realize such things in a manner that would scare people instead of making them giggle at how phony it might have looked. Let's put it this way: you could show someone the 1988 one today, for their first time, and they'd probably be impressed by most of what they saw, whereas by the time a remake was even considered, the 1958 film's FX had already gotten noticeably creaky (for starters, you rarely see the blob in the same shot as people at all, let alone devouring them).
That said, the original is still charming and fun to watch (even more so than some other films of the era whose FX aren't an issue), and that's a big part of why Chuck Russell's version works as well as it does: he had less to "fix". Linaker and Simonson's script was pretty good and fast-paced, so Russell and co-writer Frank Darabont honestly could have borrowed even more from it than they did and the film would still be an improvement due to the enhanced visuals for its ticket-selling monster. For those who never went back to the old one, many of your favorite bits from the remake - the movie theater, the diner, the hermit getting the blob stuck to his hand - are all accounted for there, too. Russell and Darabont created a number of things, of course, but the major beats are more or less identical between both films.
Naturally, they put most of their energy into making a better blob. Some of the rear-projected shots are phony looking, of course, but for every shot like that there are some that still kind of blow my mind, like when Donavan Leitch's character is absorbed and Shawnee Smith tries pulling him from it, a moment that became the box art for the VHS release (the theatrical poster went for something a little vaguer). Then there's the phone booth attack, which has an all-timer reveal ("He went down to the diner!") followed by a seamless blend of miniatures and full-sized shots, where Candy Clark gets crushed by the swarming blob on a cut so quick that you'll never notice it's no longer her but a doll in her likeness. And its acid-like effect on the people it is eating makes it far more terrifying as well, so it's not just there to showcase some makeup appliance wizardry - it's actually making the monster more of a terrifying threat than it ever came off before. It might still be a "B Movie", but when given the "A" treatment, it becomes a legitimately scary movie as a result.
It also smartly uses your (assumed) knowledge of the original to toy with you on occasion. When introduced, Leitch's Paul seems like the hero of any film - he's a nice guy, star football player, courteous to his date Meg (Smith) and respectful enough to come in to meet her parents. But if you've seen the original Blob, you know FOR SURE that he is, because two kids on a date who find a homeless man with the blob on his hand are the heroes of that one, and that's what happens to Leitch and Smith here. So it's a shock to any audience member, and a bigger one to an OG Blob fan, when he is killed a few minutes later, becoming the blob's second victim and allowing Kevin Dillon's Brian Flagg to take over hero duties. The original's female lead, Jane, is also rather ineffectual in the grand scheme of things, so it's kind of great when Meg stands up and empties a machine gun clip into the thing in order to distract it.
In fact, I can imagine an audience going nuts with applause and cheers when that happened, but that's all it can be: something I imagined. In reality, the film flopped hard in the summer of 1988, even by the standards of other '80s box office disappointments that went on to find acclaim and more fans on video (such as, er, The Thing, a financial dud that nevertheless sold more than twice as many tickets as this). I mean, it's downright embarrassing how poorly the film did, coming behind such infamous garbage as Caddyshack II and Arthur 2, as well as movies you probably don't even recognize by name, like Masquerade and Salsa. Any of those getting deluxe special editions this week? Or ever? Yes, the film found love on home video and has never been unavailable, so clearly Sony has been finding it worthwhile to keep around over the years, but when you frequently see it championed as one of the best examples of horror remakes, it still stings that it somehow managed to sell fewer tickets than the Stepfather remake that no one in the world was asking for.
I bring up the bad box office because unlike the usual "this shoulda been a hit!" sentiment for a good movie, I can't help but wonder if this film's success might have led to other updates for other 50's genre flicks that were fun enough but limited by the technology they had at their disposal at the time. It'd only be three years later with T2 that using CGI forever changed the landscape (especially for summer popcorn stuff), so there was a bit of a sweet spot at this time where practical FX guys like this film's Tony Gardner were performing wonders on a fraction of the budget that would be afforded to the CGI wizards within a few years. I feel the time for updating this particular kind of movie has passed, as the focus turned to films that didn't need to be improved (and, in most cases, the remakes proved as much) as opposed to ones where they were able to make up for this or that limitation from their predecessors. I don't think we necessarily needed more horror remakes over the past 20-30 years - I just think we needed more that were like The Blob.