If I drafted another 15
XCOM 2: (With War of Chosen DLC)
A refined version of XCOM: Enemy Unknown (Firaxis 2012) with an updated campaign.
Also a set of hero NPCs that seem to learn from previous encounters (echos of "Shadow of Mordor" Nemesis system)
Phoenix Point
The developer of XCOM 1994 looked at XCOM 2012 and said... hmm, that's not quite right, lemme give this a try. More simulation aspects to combat; i.e. if you miss a target, your shots keep going until they hit something. Interesting campaign where you uncover the mystery of the aliens.
Terra Invicta
Early release game, but from the developers of the "Long War" mod for XCom 2012. What if we did an XCOM, but didn't have the infantry tactical battles? (Eventually replaces with ship battles) Until then, instead of one resistance org, you have multiple shadowy orgs influencing nations around the world in order to take advantage of an alien threat to further their own faction's ends
Alpha Centauri
Civ2, but with a sci-fi setting. Tells a story through the campaign as various factions terraform a distant world. Design your own units, alter terrain. Game design unencumbered by historicity
Mount and Blade II: Bannerlord
Sid's Pirates, but instead of plundering trading vessels, your crew bonks people on the head until the peasants pay you rent. Other crews want this too, so you end up getting into medieval battles with hundreds of troops on horseback, with spear walls, and swinging your sword. From a first person perspective
Victoria 3
Industrialize all the things! Grand strategy of the 19th century. Build up a tech tree to take advantage of resources, while trying to appease various political factions in your nation whose interests are threatened by the increasing pace of change.
Europa Universalis IV
Colonize all the things! Grand strategy of the 14th through 17th centuries. Explore the world. Make new friends. Mug them. Become prosperous!
Fire Emblem: Three Houses
Tactics game, storyline from 3 primary perspectives. Your army is made up of a set individual NPCs with unique talents and backstories. Level them up and guide their development. Get to know them. Oh, and they can permanently die. Have fun!
Pathfinder: Wrath of the Righteous
Adaptation of Pathfinder Adventure Path. Deep story, engaging companions, challenging battles, well thought out fantasy world.
Also a Heroes of Might and Magic campaign mode? What a cherry on top
Kerbal Space Program
Build your own rocket to visit parts of the solar system in order to learn science in order to build cooler rockets. Nifty physics engine based gameplay.
Prey
Perhaps the most refined version of Deus Ex/Bioshock/Metroid immersive sim. Explore a creepy space station and figure out what the heck is going on
Into the Breach
Chess-like rogue-like strategy game, themed with mecha defending the last vestiges of humanity from kaiju.
Spelunky
Deceptively deep rogue-like platformer. Levels procedurally generated so they're new every time. Requires very precise, thoughtful movement, and has a 2d physics engine that can result in chaotic outcomes. Also every floor has a timer.
Rocket League
The best version of Soccer.
Left 4 Dead 2
Multiplayer Co-op shooter. Great if you can get a group of friends to play with regularly.