I liked it. It captured and slightly improved upon the old X-Com games, and it had good writing and felt overall well polished and balanced. I liked the art, it was well made and detailed. It did lack some flare and a lot of it was too... bland, I guess.
I'm not interested in comparing it to the new XCOM's however, since (as I've said somewhere before) I think they have deviated enough from the old gameplay to warrant their own category. And I don't consider them oversimplified. As Dragula said: streamlined, not oversimplified. Sure, some things were a bit too streamlined in Enemy Unknown. But I feel XCOM 2 is the deepest most complex of them all. The missions are varied, you have so many options in skills and gear for your soldiers, all the customization to make your soldiers feel alive (never before have I been so attached to some of them) and the complexity of the strategic layer makes it just as fun as the missions.
Xenonauts in its attempts to be an X-Com game suffered from a lot of the same tedium the originals had, though. I really enjoyed the "class system" it had, but in the end every soldier is equal just with different stats. And there is too little variation in gear and things to do in combat to really make different roles stand out. I did love breaching UFO's though, that was my absolute favorite part of the game. I hope they bring more items and maybe even some sort of skills/perks into the sequel. Other than that, missions tend to get same-y after a while and managing a bunch of bases and a couple of armies of soldiers is only fun for so long. I always enjoyed strategy on a smaller scale, no matter how much I loved the old games - they were so much fun in the beginning, then I usually lost interest towards the end when things just dragged on and on.
You should read the article I posted in the XCOM 2 thread, about Jake Solomons work with the franchise. He first envisioned a game much closer to the originals with an even more complex strategy layer.
