There are lots of good “gamers” games on sale today on Amazon: Zombicide, Small World, Five Tribes, Robo Rally, Tokaido, Ticket To Ride, etc.
Nighthawks is a free print-and-play game of space combat. Remarkably, each player needs just 16 cards.
There’s a very interesting thread over in the Redditt board games forum. The question was “What are your favorite games that take five minutes to set up and five minutes to explain.”
It’s a very interesting list, and there are quite a few games there I’ve never considered. My group often finishes one game early and is looking for another to finish out the night. There’s a good many here for thought.