From a horror perspective the film was brillant, but honestly it felt like Scott made Covenant to be a remake of Alien so he could use all the CG he was deprived of in the past to make his vision come alive and appease fans who hated Prometheus.
My greatest issue with the film is David being the 'engineer' of the egg, facehugger, and Xenomorph. It flies in the face of canon that The Queen Xeno lays the eggs and if there is no queen, a drone mutates into one (Alien Director Cut).
I could forgive David being a cook who simply discovers the recipe that creates the Xenomorphs, and that others like The Engineers and Colonists stumble on the recipe too seperately.
Overall, Covenant is a good film if you ignore the retcons, continuity issues, and the bad pacing once you are in cave with David, where the film really slows down and frankly has poor aesthetic in my opinion. The film shines at the arrival, the exploring of the planet, the Neomorph incident and in the climaxes of the Xenomorphs first trying to board the shuttle, and later on board the ship.
Honestly however, Scott failed here storywise. Prometheus had a build up to seeing The Engineer Homeworld and an encounter with them on their planet, we hardly get that but in a rushed flashback scene. Worse Elizabeth Shaw, my favorite character since Ripely is killed off as an experiment by David. Really?! She saved his life and gave him an existence beyond being a decapitated head. He'd have never been able to play biologist and bioengineer if it weren't for Shaw! But most glaring is David being the father of the Xenomorph. This is like Disney who sweeped SW Expanded Universe into Legends and said it aint canon. Now all these Alien and Alien vs Predator books, comics, games, and worse even canon films (a la Aliens, Alien 3, and Ressurection) don't jive, having been contradicted by this violent retcon/ reboot of Alien Covenant. Why oh why must good stories be called legends and not be used, and instead contradictions and continuity messes are called canon?! Ugh rant over.
Covenant is a good film if you just decide its the Original Alien rebooted. Otherwise the plot holes and continuity issues will make parts of it unbearable to fans.