Arrival was not a very good movie, IMO. My Son & I saw it. It had a lot of promise but felt slow, flat & plodding to me.
Just to be fair to our readers, my wife and I thought Arrival was one of the better SciFi movies we had ever seen.
The row behind us (couples about our age) felt like you did.
SciFi is something that rarely translates well to film barring an occasional Space Opera (Star Wars) or fantasy (LOR) we have all seen more good stories ruined than amplified. I will say it is a “thinker” so if you want action packed drama, this is not it.