You should try playing roguelikes too (google if you don't know what this genre is), i specially recommend you Dungeon Crawl Stone Soup, it's like a hardcore tactical RPG, pretty unforgiving with mistakes (but fun at the same time (just like DF, it's focused on replayability)), it has randomly generated loots, maps, tons of classes, races, strategies, and ways of dying. And what i like about it is that the devs did a really good job removing easy/boring/cheese tactics from the game (which are pretty common in many roguelikes despite their initial difficulty).
I did play NetHack at one point in my life which I enjoyed a lot. The sound of Dungeon Crawl Stone Soup really has really peaked my curiosity and I look it up after this post. I never got far with NetHack, a few times I got to the first underground towns but mostly I got killed because I was idiot enough to take on those things that petrify you in melee combat. So one move you go to attack: Petrify, about a million turns later you're dead from starvation. NetHack was one of the few games I didn't research on though and just went with it which is probably why I ended up kicking the bucket so easily(or just temptation to try and take on those petrifying mobs).
NetHack was my first roguelike too, it's awesome but it has little ingame information, and it's pretty hard to advance without spoilers (which i hate to use), and once you are spoiled it's easy, specially if you use cheese and boring tactics like
pudding farming or
nurse dancing.
OTOH, Dungeon Crawl have extensive ingame information and documentation and you are ready to "have fun"
after playing the tutorial (you can learn from playing, when you die, most of the time you know you made a mistake last turn, 10 turns or 15mins before). It has almost no cheese tactic, and the UI, despite being
ASCII is superb (It has a superb
tiles version too, which i recommend, no need to be masochist).
IMO, DC have the best basic features to introduce gamers to the roguelike genre, and NetHack, to scare them away from them
(and DC is actually harder since there's no "panic button" AKA 1 turn life savers like insta-teleport to safety or (scroll of) genociding enemies).