vulchor: Congrats, it really is a fantastic game, I thought it was much better balanced than the original X-Com games. Now, maybe before you start XCOM2, you instead could install Long War for XCOM 1 and have a whole new experience. Long War really is the ultimate way to play, in my opinion.
badon: Why is it the ultimate? Is that mod compatible with OpenXcom?
no, why would it be ? openXcom is for the original games, LongWar is for the new XCOM from Firaxis.
Long War adds a lot more depth and complexity to the game.
More classes, abilities, items. improved, extended psionic abilities. battle fatigue. changed air game that requires much more careful resource management.
aliens (and EXALT) do their own research and will get stronger throughout the game thus keeping the difficulty up even as the player gets stronger.
it is pretty much a free expansion pack to the base game. And if you liked XCOM I can only recommend giving Long War a try.
as one of the Lead Designers from XCOM put it: "vanilla XCOM is basically a 20hour tutorial for the real thing (Long War)" :)