You shouldn't remake a movie, or serve a prequel to an old movie (two sides of the same coin) unless there's something there to explore. Alien had some questions, and luckily no one wanted to answer those questions. Questions that ultimately, Daemon and Ridley decided that the Space Jockey storyline had something there. While they answer some of these questions, they also leave a lot unanswered and ultimately splinter the Alien franchise even more.
The Engineers are the race behind the Space Jockey. The Engineers are very much our creators, and the mission that launches the crew into space and the audience into this film is to meet their maker and find out ultimately who are The Engineers. Doesn't take long for the crew to find out that The Engineers are extremely pissed off. If the dead bodies and such don't warn you of this, or the black killer goo, or the arm breaking tentacle monster. I started thinking this crew was completely clueless -- to see death and destruction all around them then they decide to poke at the aliens or play around with things they don't understand. You can start to see why The Engineers are so mad.
Alien was a great horror movie because ultimately it did things others weren't. The whole chestburster scene is perfect, because you're not expecting it. Similarly, the whole C-Section scene works because alternatively -- you are expecting it! To see Elizabeths belly inflate and deflate you're thinking "Shit, anytime now" then when the machine surgically removes the alien beast, it's still a shocker because it still leaves shaw alive but confined with this tentacled beast. It was a great scene that played with our expectations.
David (Fassbender) is the star here. Noomi comes off as naive and a little too overwhelmed. Logan Marshall Green was okay, but played like a thrill-seeking scientist. Just didn't mesh with me. Irdris Elba was great as the ships Captain, Janek. Another real let-down was Theron, who was good in her role but it was far too predictable. Considering one of the earliest times we see her they're questioning her regarding ulterior motives.
So between the tentacled beast, the black goo, and The Engineers; there's a lot of new aliens in this movie. It gets jarring to have so many players. In fact, I'm surprised that they didn't make it more efficient. The Engineers are the stars here, but the black goo never really gets explained, and while the The Engineers get a lot of screen time; it's that scene in the beginning that ruins them. As it basically shows how they're being destroyed by their own creation.
More questions are left unanswered. Shaw wants to know, why The Engineers want them dead. I know, because in the beginning of the movie it SHOWS THEM DYING FROM WHAT IS PRESUMABLY THEIR OWN CREATION! The Movie literally shows us, the answer to a question at the beginning of the film. The Engineers obviously have lost faith in their ability to handle their creations and are now going to essentially clean up their 'mistakes'.
Am I invested? Partially. It seems like this is all a ploy to get a sequel made. Will I see it? Probably. Problem is, I just don't care about the question of why The Engineers want humans dead, I can safely assume that they think humans will turn on them like the tentacled monster or the black goo. This movie could've been more effective with its story and simply been a prequel to Alien. Instead it's now it's own thing where we're exploring the backstory of these Engineers, while it's also trying to connect this tale with that of Alien. It may be explored later, but I can't judge a film on what it can be, I can only judge it for what it accomplishes.