As of at least 3.9.1, using this mod in a playset make it impossible to create or edit a custom empire. On the empire creation screen, a tooltip with the warning that the empire's ruler has a class that's incompatible with the government's authority (no matter what government or ruler class you switch it to) blocks it from saving and can't be resolved in-game.

I hope it will get updated. I really like it.

I like it though the planetary rings and other powercreep has done a lot to make these things less relevant.

hey, just a heads up your mods not compatible with Ethics & civics: bug branch because you overwrite the government authorities in that mod
https://steamhost.cn/steamcommunity_com/workshop/filedetails/?id=2517213262