I think I'm unfairly critical of the Alien franchise because the first movie is so astounding. It's my second favorite film of all time after Jaws. I honestly don't like anything to with Alien after Aliens and even that I put a few dozen notches below the original.
The only part of Prometheus I found even borderline interesting was David, who ironically was the only character in the entire movie that behaved like an actual person. That's been Scott's problem throughout his career and I'd wager every movie he has made with a synthetic lifeform, the synthetic lifeform was the most human character in the film. I mean, for christ's sake, he managed to coax a bad performance out of Idris Elba in Prometheus, which is hard to do. He's just not a very good director of actors. He has composition in an 'every frame is a painting' type of way, but he's never been able to coax believable performances from his actors.
I think he'd really make a better DP than a Director.
Prometheus was a pretty mess with an incoherent script and awful performances all around. The fact you see imbeciles like that guy above claiming 'only dummies don't get it' shows the type of depths people have to sink to, to defend that abomination. Ridley has simply gone to the well too many times with Alien, whether as Director or Producer and needs to just come up with a new idea already. The Alien franchise is starting to feel like Star Wars now, although that comparison does explain the type of fanboy following it's gained (and grown) as the series progressed.
Alien 3 is watchable, but far from good, just because Fincher at least did something a little bit different with the material. But if I want to watch an Alien film, I'll just watch Alien. I don't need a dozen sequels to 'explain' shit that Scott never thought through in the first place (and which were therefore interesting to think about).