TL "Registering Members" Help needs to be updated

We’re a newly chartered TL troop, initially the Charter Org Rep was the only one with any privileges. “Manage Troop Members” was added to myself. I had Unit Access as a member of the committee but was not able to send the emails.
We’ve gotten past it by adding all privileges but, what is the ‘correct’ and ‘minimum’ Access and combination of Privileges to be able to send the emails?
Next TL troop would probably love to know…