I don’t have a straight up list to offer you, but https://lemmy.dbzer0.com/u/db0 has made a software for looking up instances with high amount of users but low amount of posts called lemmy-overseer. https://github.com/db0/lemmy-overseer
On github you can find link to their running instance with API documentation.
I have not personally used it, so this is as far as I can point you :)
I was about to buy this but apparently they are planning to change their current anti cheat software to FaceIt which does not support Linux. EAC is still used for upcoming selfhosted servers but ranking up is disabled. I’d rather not feel like being considered as a second class citizen so I’ll have to skip for now.
Other than that the game looks fun. I prefer to look in to the current state of the game rather than the promises of future content (which kind of contradicts my anti cheat point but eh), and I feel like the current price would be worth it even though it’s an early access game.