First and foremost, the amount of bugs this game has, it really feels unfinished and unpolished.
It's really, really boring. There's not a lot of strategic options, so every encounter is pretty much the same routine due to lack of strategic potential. Some characters are so much more rich and interesting than others, really unbalanced.
Cover doesn't mean a thing in this game.
The assembly projects are really weird, you just upgrade crappy material instead of getting interesting stuff. It feels they were really lazy.
The lack of customization is insulting. No character development, at all. Everyone is either black or an alien. Quite the racial balance there.
Don't buy this game, play XCOM 2: Long War 2 instead.