Not only is the entire execution buggy, it is actually broken from a UI/logic stand point. It spends all its time bouncing around what it's trying to do, honestly 1.1 was better since it didn't implement it as profiles, but as groups having permissions, then groups having unique permissions in individual boards.
Add to that, that if you ever want to add any permissions that don't fit the "general or board" structure, in SMF you are entirely left to your own devices. Aeva, SimpleDesk, Project Tools and many more mods ended up implementing their own permissions structures because SMF doesn't have one that's extensible.
Then, for an encore, consider post groups on their own. Why are they special? They're so special, they have pride of place up there with primary member group in the database. Really, that's something that will need to change someday.