My retro slanted suggestions:
Free Stars: The Ur-Quan Masters is one of the greatest games of all time and it’s free. There’s a Steam version, but I think you lose a few of the original music tracks in exchange for easier management. They’re also crowdsourcing a sequel, about 30 years later.
https://sc2.sourceforge.net/downloads.php
I’d also recommend UFO 50. It’s a treasure trove.

Say it with me, everybody!
Get fucked, fascist!