Aliens don't wander the map - they stay still in a little clump until they get visual. When that happens, they get a round where they are allowed to move but not fire. Also, aliens are extremely deaf. You can have rockets blowing out walls but, until the aliens actually see you, they'll just ignore it. (To be fair, most games have deaf enemies but somehow it seems more silly in this game.)
The interface is the real pain for me in this game. The camera is just awful! You can only spin around to one of four angles, the zoom is weak, and the camera gets really confused if you get near the edge of a map. The interface is also huge - yet still needs to scroll text because the fonts are even larger.
The manual is a terrible joke. You'll learn far more from the tips you'll see when loading missions and the game. (Woe to those who have the game installed on an SSD!)
On the plus side, though, the game is REALLY fun! Every time your squad seems to have gotten strong enough to take on the aliens, some new critter pops up and sends half your team to the hospital. One dumb mistake can end a favorite soldier's life for good. Well, OK, if you want you can always reload and try to keep them alive but don't do that too much. The game is a lot more exciting when you pay for your dumb mistakes.
The game has got some bugs so I wouldn't try Ironman yet. I've had it hang on me a few times and taking a Steam screenshot really mangles the game for me. There's also some things that seem like bugs but really aren't - like shooting through walls. The aliens' weapons are strong enough to blast right through a wall but the game sometimes forgets to destroy the wall when that happens, making it seem like the aliens (and later, your own squad) are cheating.
P.S. If there's a way to bring a nation back into the XCom fold, I haven't seen it. Maybe if I start protecting other countries in the same continent?
P.P.S. Yep, every rookie does seem to have the same stats.