It is surprisingly a decent thriller movie. Entirely watchable without needing any previous movie but more interesting after watching associated movies. Not many jump-scares and some of them were screaming 10 minutes before that they were coming at you. There are philosophical questions. The way these questions are set, make the viewer more interested in the question rather than the answer.
The first plot twist is that there are 2 androids. The second one that the 2 androids lead the movie with quality conversations. The third plot twist is the third plot twist! In the end, covenant is a thriller movie. Stupid decisions are made by humans. They are colonists, the elite of humanity, boasting IQ and reflexes over 9000, problem-solvers and chosen to be able to cope under difficult circumstances but still dumber than bonobos when their lives are at stake. No one should watch a thriller movie expecting dumb decisions to be absent.
What bothered me the most is the fact that the xenomorph grew in size without obtaining any mass. Please do not argue about that conjuring up Sci-Fi movies stuff. Even science fiction can not transform air molecules into tissue, bones and saliva constantly dropping from a 2-meter-150kg beast.
It needs to be noted that sometimes, the beauty of such thriller movies is when the viewer does not really know who the actual protagonist is, until a certain point (usually after half the movie). Not a perfect movie but there are nice touches all over and of course, it keeps you on edge after a small ramp up on the rhythm which in the end makes this a successful thriller.
"David: I'll do the fingering."
"Oram: What do you believe in, David? David: Creation."
"Walter: When one note is off, it eventually destroys the whole symphony, David."