Original Ending Would Have Made This Movie Worthwhile
If you go to the IMDb Trivia Section, there is this:
"Originally, a different beginning and ending to the movie had been partially filmed, which would have shed more light on the Thing's backstory. The prologue would have shown how the alien pilot purposely crashed the ship on Earth, and then committed suicide. Later, an alien that was in the process of becoming a Thing would exit the ship in order to kill itself by freezing. At the end, as Kate (Mary Elizabeth Winstead) enters the ship, she finds the interior littered with dead aliens, either dismembered, burnt or in a state of transformation. In the central area, she sees the last alien pilot hanging, with its throat slit. According to director Matthijs van Heijningen Jr., the implication was that the alien race piloting the ship was collecting other alien specimens. One such specimen was a Thing, which had broken out of its confinement pod, leading to a massacre among the aliens and other specimens similar to what happened at the Norwegian base. The Sander-Thing, having taken the form of the pilot, suddenly attacks Kate, but she holds it back by threatening to use a grenade and blow both of them up. Then Carter (Joel Edgerton) enters and uses his flamethrower on the Pilot-Thing, to fool Kate into believing that he is human. After early screenings, the studio didn't think the Pilot-Thing was scary enough, and the climax was becoming too complicated, with Kate trying to stop the Sander-Thing as well as discovering the Thing's backstory at the same time. So the backstory was omitted, a new computer-generated Sander-Thing was inserted at the last minute, and a Tetris-like animation was added to the scene where Kate enters the central area to hide the dead alien pilot."
https://www.imdb.com/title/tt0905372/trivia
So, since this prequel doesn't do much but repeat the same action beats as the original, THIS would have actually been something original that the prequel could have added.
Look at the Pilot:
https://www.youtube.com/watch?v=CQO-yx-yLHQ
A look at the practical effects:
https://www.youtube.com/watch?v=fBzpT7VmSaU