I fully understand what your trying to say, and point out about the members groups, and the Moderator thing.
But while there may be a good case as to why the Moderator option should not be in a members profile. Because you would also have to assign to which board he covers. (Mod could sort that out)
I do not agree on only allowing certain members groups access the Categorys created. This is why!
In terms of power, you have!
1. Admin
2. Global Mod
3. Moderator
So you should be able to create Categorys that only give Admin and Global Mods access. And Categorys that give Admin, Global Mod, Moderators access.
But for this to be the case, there would have to be the option to make a category Moderator accesss only. Not as it stands now were if you choose Global Mod, it allows both Moderators access and Glbal Mods.
Because a Global Mod is a step up from a Moderator. So why when a category is made Glbal Mod access only, should a normal Mod be granted access. Sorry but thats wrong!
Phew!