I'd even go as far to say that of all the retrospective looks at the franchise, that Aliens is often left out a bit more now too. Not as much as Alien 3 and Resurrection are, but everyone has gone crazy for the original Alien more lately. Probably partly to do with Sir Ridley Scott returning to the franchise a few years ago, as well as the recent build up and good word of mouth for Alien: Isolation.
I would love both an ALIENS Vault and an ALIEN 3 Vault. Hopefully we'll see them someday.