I never thought I'd complain that there is too much to do in a video game. I don't mean Ubisoft-like optional side quests and collectables, but stuff you have to do to complete the game's story. Alien: Isolation is just such a game.
Honestly, what The Creative Assembly did with the Xenomorph itself and the AI that powers it (this channel on YouTube has some fascinating videos on it) is pretty amazing. The atmosphere of the Sevastopol space station itself is very creepy, and the aesthetic is keeping in line with the films really well. The first time you see the Alien, too, is pretty special and isn't signposted at all.
However, there is just so much busy work in this game! Things that should take two steps instead take five. This is exasperated by the fact that the game want you to not engage in combat, so you're sneaking around all the time, thus moving slowly. Add to this that save points are spread out fairly far apart so if you do get killed while doing one of these many steps - and you will - you have to then go and do them all again. Oh, and sometimes the game makes it really unclear exactly what you are supposed to be doing, so you'll be ambling around trying to figure out what all these steps are, getting killed and having to restart in the process. Ugh!
The game drags on much, much too long. The last half of the second act/ start of the third is incredibly bloated with useless quests that really don't add anything to the game. I reckon if they cut out everything between taking out the Apollo AI and setting up your original ship, the Torrens, to dock with the Sevastopol, and then still streamlined what was left, it would have been a much more enjoyable experience. Even your very last actions of the game contain more fussing than is needed.
The biggest problem with this, apart from the tedium, is that it drains the Alien of all threat. Eventually you just get sick of seeing the bastard because you just want to get past this annoying series of "go-here-do-this-go-there-do-that" tasks and move on with the story.
In the last third or so of the game some new enemies are introduced that, well, I don't really know what the point of them was. They are stronger versions of ones you've faced before, but for the most part they don't offer any extra challenge. The story reason as to why they are there does make sense, but it just feels tacked on. It was one of my least favourite parts of the game and really had me wishing the Xenomorph would show up and kill everyone (which it did, after a while).
Full disclosure; I'm not a huge Alien fan. I much prefer AlienS, and I love the Xenomorph design, but I wouldn't say I'm a huge fan of the franchise, although I have seen all the films. This is a long way of saying that perhaps I'm not exactly the target audience for this game and perhaps your mileage with it will be greater if you are a big Alien/s fan. With that said though, I do think the game does a very good job of achieving the feel of the film on which it is based. Because it was based more on Alien than Aliens I can see Creative Assembly tried to achieve that "quiet horror" of the original film with things on the space station going wrong that you have to fix, rather than having aliens all over the place like the second (and third, and fourth) film. Unfortunately, a video game is not a film and the balance here, I feel, doesn't really work. Or, at least, they needed a lot less of the "quieter" moments. I also found the ending to be rather unsatisfying, although it is in line with the ending of many of the films.
For those who like stealth-based games, particularly those with a horror slant, or the Aliens franchise in general I'd say this game is worth checking out. For everyone else...I'd say it's still worth a playthrough, just be aware that there is a hell of a lot of bloating going on.
TL;DR: A good game with some really wonderful AI and some great moments that is weighed down by excess bloating that makes it a chore to see through to the end.