[Dealing with Reapers]

Always make sure you have enough in reserve for reaction fire, and try and move your soldiers around in reasonable size squads. I split mine into fours, that means that they can cover more angles and you get more chances at knocking the Reaper over before it makes contact.

[Convince me to buy Xenonauts.]

Uhhh honestly it's not a very good "game." The midgame in particular is very repetitive and if you play right you can basically smack down all the dramatic events like terror missions by intercepting. Basically interceptors are way OP and ground battles your troops are way under powered. And the alien psyche attacks are more griefing than fun. I still appreciate the effort but yeah the game is not as good as the original xcom even with the new graphics.

To be fair, all of those things were also true in the original UFO. It took a little longer to get to the point where you could knock down terror ships so you'd have to do some terror missions, but once you could, and you had hyperwave decoders up and running you could effectively halt basically anything the aliens tried to do, and the mid to late game was equally static.

And the in-battle strategies are really very similar. Exactly the same core tactics of not advancing into the unknown without TUs to deal with what you find, moving in groups so that you can confirm killing anything you find without it getting a turn back, managing who and what the aliens use their reaction fire on, etc. The repetition is an inherent part of the game, once you've killed one battleship full of Mutons you've killed them all, with the only slight variation being where the guy with the blaster launcher will be standing this time.

Really, Xenonauts plays a hell of a lot like UFO with a lot of quality of life changes.