For me, I'd have to say Old School X-COM (UFO Defense, TFTD, X-COM Apocalypse to an extent). I love them in a way that I just do not enjoy NewCOM, but the interface was quite possibly based on the recovered works of a 13th century scribe, and is very difficult to get used to for an unfamiliar player.
I'm not sure I get this one. It felt pretty streamlined last time I played it. I mean ig Into the Breach's graphics looked better but that doesn't really invalidate the original game imo.
I hadn't had any caffiene yet and just wanted to talk about FTL.