I'm not sure how apt Game of Thrones is for an Alien comparison. GOT functions due to its expansive cast, locations, etc. which all lend to its complex, multi-layered story that branches in numerous directions at once. Something like Alien, however, is much more intimate, personal, and claustrophobic.
I think that the Alien films function as well as they do because each and every one takes on an entirely new tone and lives and breathes as its own unique piece, standing on its own two feet. I would love to see that sensibility reflected should Alien makes its way to television, and I think a True Detective-esque anthology structure would be the perfect way to explore that.