The main criticism of this film,from most reviewers,seems to be it's slowness,or lack of any real action.
I think this is unfair. Those beloved of all action blockbusters will be disappointed and should look elsewhere.
Even though it features an unpleasant alien I don't think it can be regarded as purely a horror film,or even a sci-fi one.
For me it was more of a character study. Much time is invested in Ethan's state of mind,how his relationship with the creature informs his decisions and,ultimately,how he resolves his own demons.
So it's slow,thoughtful and considered,but given it's costs,it was an impressive effort by all involved.
(I'd like to know what they have in store for the future.)