@CrazyRocky this is one of those interesting discussions where if you ask 10 people you get 11 answers. For me one issue is that we are mixing titles and functions. For example, as a typesetter I usually want the function of an Administrator because I (me personally) need to be able to make changes to settings and adjust text. I realize that not all typesetters do that.
I definitely think that the role of Reviewer should be separated and given a lesser function (as you have defined).
Having said that, I would prefer to just use the titles: “Consultant” and “Reviewer” with the definitions that you created. Someone who is a typesetter could be given whichever role the team and typesetter deem correct for that situation.
So, in the end we end up with five titles/functions:
Administrator - add notes, edit text, change settings
Translator - add notes and edit text
Consultant - add notes and have ability to act as a temporary administrator
Reviewer - add notes
Observer - only receive changes to the text
In any given context the Archivist or Typesetter can be given the appropriate function for that context (reviewer, consultant, or administrator)