As a sequel to Alien, Alien Isolation works better. Being Alien is existential space horror while Aliens is an action movie. Alien Isolation also expands on Alien in an interesting way, giving it greater scope (being set on a space station rather than a ship). They could pull this off in 1982, as Outland came out the year before and was basically Alien Isolation without the alien. But no, I'm glad history turned out the way it did, but I consider Alien Isolation to be the true sequel to Alien.