Batch of comments on some things.
First of all, Muton Berserkers are a major pain!
They advance every time they get hit, have a lot of health, and do big melee damage.
I've had the UI become absolutely horrible at times. For example sometimes the game ABSOLUTELY does not want me placing a unit on a perfectly logical spot.
The UI can be a pain - watch out any time you are trying to move a unit to an overhang. I get a lot of flickering, and half the time it will send my unit down in front. It seems like you can make these moves easier by rotating the map and trying again, but I had one spot on a map that I absolutely could not move into, even though it looked perfectly valid.
without Ironman the game does not autosave. A CTD last night cost me my game that was steadily falling apart but I was still way into.
You have to go into the Advanced Options when starting a game, and enable autosave. Which you need to do, because there are some (PC) menu bugs that have forced me to alt-tab, kill the game & reload. At times, the UI menu options will be borked - for me, it always seems like the base pause/save/load menu just will not come up. That's happened to me about 3 times, and I was able to get back to the latest autosave. Battlefield saves are at the start of every turn (so if the aliens kill your guys, they are already dead in the save), but I'm not sure how often the Geoscape saves happen. Probably when you hit a research/production event, or maybe daily.
Overall, there are some glitches & bugs I really hope get fixed. Sight can be a pain, since the camera auto-adjusts when you're near the map edge, or to a set height. It makes it a pain when you're in a UFO, have a 3 story building to go through, or you're trying to move someone to a certain point in a varying height map. I really wish you could force the game to adjust to a level, like in the original. The menu bugging out is a pain, and I had to kill the game one time because it froze up (or couldn't decide what to do) on Alien Activity. I also wish they'd incorporated the UFOpedia from the original game - this has no in-game database of your stuff, and you have to check each of them out to see what they do. But still, it's pretty solid otherwise.