The players who top the leaderboards and have discovered everything in the game all hang out on the Discord and have had a lot of great suggestions over the years--that's where a lot of adjustments come from on top of my own direction for expansion (I hang out there daily as well). There's already waaaay more planned and possible than will be eventually be implemented, I'm sure, but it's not an open source project so won't be on GitHub (aside from what's already there, anyway, but that's the protobuffer format for public reference by third-party tools
).
Also there's the in-progress format for data sharing with third-party Cogmind-playing AIs, but that's not yet on GitHub, currently only barely documented and in a fledgling state since only one person is using it.
But anyway, the hidden channels on the Discord (access on request due to spoilers) are where the vast majority of suggestions are fielded and hashed out. There's also a lot of collective knowledge there with regard to what's feasible, and my opinions on various ideas. The original plan was for all that to be forum-based so that it's easier to organize and reference, but here we are years later with hundreds of thousands of chat lines instead xD. Oh well, the process is certainly more fun and lively that way!