NAM
World War II GI
Spellforce 3: Fallen God
Spellforce 3: Soul Harvest
Prey - Mooncrash
Wacraft 1 (due to the incoming delisting)

I've just purchased MechWarrior 5: Mercenaries - JumpShip Edition today actually. I've played a little bit of MechWarrior Online in the past, but didn't quite enjoy the experience since I believe I was forced to play in the American server since the Asia server wasn't as crowded (or if it even existed at all lol) so I had to play through the lag as well (I live in Asia). And now that MechWarrior 5: Mercenaries is a singleplayer game, I'm hoping I'd get to relive the immersion I had with the pervious game with a better experience. Still downloading the game now.

The game is good, and there are plenty of nexus mods that are compatible with the GoG version.
That's a big plus.

I only liked the last ones, the others are dispensable and shouldn't be mentioned.

-Deepest Chamber: Resurrection
-Star Trucker
-Songs of Silence
-Anger Foot
-Dream Engines: Nomad Cities

All purchased with discount.

Total Annihilation:Kingdoms + Iron Plague
Star Renegades Deluxe Edition
Star Hammer: The Vanguard Prophecy
Old World
Solasta: Crown of the Magister
Symphony of War:The Nephilim Saga