So Firaxis came out with their X-COM remake and it was good enough for a sequel, but it was a little simplified & dumbed down for streamlining's sake. Xenonauts started work before X-COM and it falls in a sweet spot between hedging more towards the complexity of the original, while updating the game/UI just enough to feel fresh and updated. It doesn't have nearly as huge a budget as firaxis musters, so it's 2D with relatively simple (but effective and pleasantly depressive) graphical design. But it requires more strategic depth than the flash-boom-pow Firaxis focused on; more troops, more deadly enemies and more actions per turn. It's got actually worthwhile base building, with an engaging air-combat dimension that Firaxis bailed on entirely. While the plot/characterization is done more subtly, the writing is quite good and putting an alien invasion in the middle of the cold war sets a very believable and engaging tone/plot arc that I don't think the game gets enough credit for.

***king aliens with death rays just landed, you've got a couple dudes with M-16's wearing paper mache, the chances of them making it out of this alive are VERY SLIM, and you can see it on their faces. Xenonauts sells this sense of peril MUCH better than the other Xcom reboots managed.

I really liked Firaxis' X-COM & X-COM 2. I think maaaaybe X-COM 2 edges out Xenonauts, but they had millions more budgeted to get there. Xenonauts is much more bang for your buck, and Goldhawk did fantastic job for such a little company.