X-Com 1 and 2 (new versions) are great games, even if they moved away from the large squad slaughter that was Enemy Unknown, terror from the deep and partially Apocalypse. I personally really enjoyed looking at black sections of the map and thinking "that will cost 3 rookies to explore"
Everyone is aware of the "95% to hit meme" around X-Com, and if you've played Phoenix Point, the difference is especially jarring. If you haven't, aiming in that game is purely a probability cone, so standing point blank next to an alien means something. In X-Com it doesn't mean diddly squat.
I finally figured out what the problem with X-Com is, and why it's always uniquely frustrating. With it's pod based mechanics, fake stealth and drip fed enemies. What you are seeing on screen has no relevance and only serves as a distraction. Being right next to an Alien and missing is irrelevant because where the character and alien are on screen do not correlate with the game.
X-Com is, for all intents and purposes a very fun card battle game. If it were a Dos prompt game, with exactly 0 visuals, nothing would be lost.
Try it next time you play, completely ignore the visuals and imagine your character as a card drawing a dice based attack against another card.
This has been my go-to strategy.
Have a dedicated demolitions expert and another squad mate who just lugs around high-explosives in his backpack, and let the demo guy just place explosives everywhere and level the stage. It's also how I would approach entering into alien craft: use tanks and just blast the walls down for a couple of turns and have multiple squads surround the craft. No need to worry about getting shot in the face when entering through the front door.
The only tricky tactics is later on with the battleships and their teleport entrances -- but you can still toss explosives up the teleporter and kill anything on the upper floors. Absolutely loved that about the original trilogy.