The premise of Alien Covenant is quite standard but nevertheless interesting. A spaceship is on a long voyage to a colony world, and something happens midway that causes them to interrupt their trip. They receive a message from a place where there shouldn’t be people, so they decide to investigate. What happens next is the most predictable plot in the history of predictable plots.
The characters exhibit very poor decision-making skills, things that common sense should prevent them from doing – but they do them anyway. They explore an alien environment without protective gear, express no surprise at the identity of a new character, separate from the group, etc. Pacing-wise, it’s pretty good and the visuals are very Giger-esque – perhaps a tad too dark – but great nonetheless. It’s a lot more of a traditional Alien movie than Prometheus was – and you do find out about the origins of the Xenomorphs.
Alien: Covenant is not a bad movie but it does struggle with presentation. Its characters have unbelievable behaviour and its main antagonist doesn’t have a clear motivation other than ‘crazy’.
Prometheus 2 probably has one of the dumbest colonists in the Galaxy. Not only do they just breathe in the atmosphere of another planet just because it has vegetation, they have rather idiotic behaviour for most of the movie. Here’s a list:
Prometheus 2 seems to carry the torch of scientists/explorers being severely, and lethally, stupid. Nevertheless, it was an… ok movie.
As far as the predictability goes, it's really plain to see. In Prometheus 2, Fassbender’s Walter character meets his David character from the previous movie, who came to that planet after the events of Prometheus 1. Elizabeth Shaw (Noomi Rapace) and he found the Engineer's planet, and David proceeded to shit on them all with the black goo from Prometheus, wiping out the creator-race of humanity. They were just chilling on their planet this whole time, wearing robes and being all 'ancient technological civilisation' and shit.
Anyway, David, being super evil because reasons, is at odds with Walter, who is nice guy robot. In the end, they fight because David is crazy and has some weird god complex. Their fight is never shown to end, after which Walter is seen running out of the building they were in to escape with his ‘friends’. Obvious face swap is obvious - not that this is a bad plot point. The execution is just terrible. That's one example of multiples.
On the bright side, you get to see the origin of the Xenomorphs, which is great, though maybe the act by which they exist in that universe may be less so.
If you’re incapable of suspending your disbelief, this movie will probably anger you. If you’re okay with predictable plots and just want to see Xenomorphs running around being evil, then you’ll probably enjoy this movie. Also, Michael Fassbender’s face.