This is what Enemy Unknown should have been. Fantastic.
Don't misunderstand me, I loved Enemy Unknown but it lacked many aspects of the classic XCOM series (that I recall with massive affection) but it's all back (plus a bit more) in this new game. I grabbed it off STEAM so was able to crack on first thing Friday morning of last week.
The new Mechs are great fun. They are tough but not invincible and, like all troops, you don't want them to die. Added back now is the base assault mission where the aliens attack your base. This happened to me last night and I almost wet myself! I hadn't read about that feature coming back and was utterly delighted. Your troopers can now get medals too. They are not just bling either, they confer bonuses to sight, accuracy, will power, etc. All good. The aliens also have some new units. The seekers are fun and remind me of those 'tentacally' things from the Matrix films that attack the ships. They have their own mechs too which are tough as hell.
Lastly, there's also the problems caused by counter-XCOM badies (EXULT)who try to disrupt what you do. You send single agents on missions to combat their meddling and then send a team to extract them. It's good fun and pits you against human adversaries with the same (basic) weapons as you. Nice touch I thought. Also the tech tree is much larger, building satellites and uplinks appears much tougher (on Normal/Normal) and you must capture the new material 'MELD' in order to upgrade those Mechs and psychic chaps. This is indeed a new game, not just an expansion. Well worth every penny.
The overall feeling is of a much richer game which is much tougher, you're really battling against the odds now and victory will therefore be all the sweeter.
I'm not done yet. I've taken out the alien base but there's a way to go. More fun in store ...I hope!
Can't wait ...