Three issues that come to mind from when I played:

The gun... if you ever played right at the beginning with the people you could take down that drop their guns... that you're not allowed to touch because I guess they've got cooties or something, really broke the tension & was the first introduction.

The length made me disconnect with the story, to the point a didn't care at all about anyone, was sad Bout the Scottish guy but by the end I felt I could very easily have dropped the game & been fine, I can't even remember how it ended.

The ai, as others have mentioned, was somewhat prone to breaking. For me it was the opposite issue to others & I guess (in part wanting the game to reach its conclusion) my own fault. I found that when the alien does its intro animation to tell you it's in the area (the music would also join in) you'd be locked in place for a small portion of it but then I guess they freed up your controls to go hide, like some game of alien hide & seek & the alien is counting. Instead force whenever this happened I'd just b-line sprint to whereever I needed to go. So by the time the alien was free from its forces animation I was long gone & the ai didn't really know how to handle that & would scramble to do something.

Overall I liked the game & would love something shorter, maybe based around the new movie or just completely removed from the movies so the game doesn't live in the shadow of any movie.