Hey, really glad you liked it! You should definitely try making some lefty gaming stuff! In a really general sense, I guess there are two things I try to focus on for all of my games (with different levels of success). First, I try to make my games accessible to as broad an audience as possible (making the language clear by minimizing lefty jargon, making sure the games will run on lower-end machines). I can't remember the exact quote, but someone wrote that if your art is inaccessible to the working class, then how can it be revolutionary?
The other thing I try to do is put forward positive/optimistic visions of the future. It's really easy to be pessimistic about the future of the planet, but I believe that one of the ways capitalism reproduces itself is by convincing us that no other world is possible. So it's really important for leftists to push back against that and show how a better society is within our grasp.
But yeah, that's some really general thoughts. I'm more than happy to discuss game ideas in more detail or look over drafts, just hit me up at colestia3@gmail.com
Best of luck with the game design!