I’m excited to see suggestions for this as well. For the past six months (after moving in with my girlfriend), I’ve been moving from mostly playing 4-5 player games to mostly playing 2 player games.
So far, the two best experiences I’ve had have been with Yomi and Puzzle Strike.
Yomi takes 20-30 minutes and almost no table room. It’s basically Street Fighter the card game, but extremely easy to get into. IMO it plays best in “best of three games” style to offset some inherent luck.
Puzzle Strike takes 30-40 minutes, takes up a huge amount of table space and has probably a 10 minute setup time. We only crack it out when we have 1-2 hours. I also think it’s best to play “best of three” because you get to figure out how to combat your opponent’s character and how your character works with the current available actions. It’s my favorite Dominion-style deck-building game, but IMO is not worth playing with more than 2 players.
We also occasionally play Ticket To Ride on the Nordic map, and Carcassone (as well).
Lost Cities is always a big recommendation for 2 players, but I really disliked it (one of my least favorite Knizia designs). I will back up the LOTR: Confrontation board game. I don’t own it, but I’ve played it a bunch. It’s great! We also got into LOTR: LCG for a while. It’s quite fun, but I found it a little dry. Pretty painless setup, takes up not too much table space, and plays quick.
I’ve been looking at Seasons lately which is a new game with a drafting mechanic that’s apparently best with 2 players. I haven’t played it, but it seems to be getting good reception on BGG. Anyone given it a shot?
As a side note, my father put Castles of Burgundy on his Christmas list this year. Anyone played this? He’s pretty new to board games but found it on BGG and thought it sounded neat. I’ll probably grab it for him anyways, but I’d love to hear opinions on it.
EDIT: I should probably mention that my girlfriend is annoyed with how sexualized the characters in Yomi are. It’s sorta standard Japanese fighting style art. It hasn’t soured her on the game, but she disdainfully points it out periodically.