I can help a bit with the love/hate on this game. I have both.
This game is NOT like the original UFO series. This is a more cinematic, focused game. Each combat encounter is equal 2+ from previous games. You have fewer units, fewer techs and fewer everything - but those things are more impactful.
This game is essentially a complete remake. It keeps the same ideas, but takes it into a different direction.
The combat is also COMPLETELY different. Each shot is equivalent to several turns' worth of shooting from the previous games, so you have to make it count. The 20% shot is NOT a good idea. What is a good idea is to break line of sight completely, and focus on sniping/flanking. Risky shots are only good later in game, where technology is better and you have more health/damage.
Impossible is simply unfair, and I don't recommend it unless you know the "meta-game". It does have superior spawning mechanics, but it makes me very prone to ragequitting.
Thin-men are (I figure) specifically designed to weed out rookies. They are the game's breaking point, and if you can survive past that, you will be just fine.
Also, as I learned from Let's Plays (
link to my favorite) the game demands a LOT more "losing". You are SUPPOSED to lose countries and units, and survive regardless. The losses are more necessary, and more painful, than the original series.
At the end of the day, it's 60% tactics, 20% mechanics and 20% cinematic enjoyment. It's a good game for what it is.