As Arthur pointed out, we ought to start discussing the covenant charter and what we want it to provide. Here is a list that I cam up with of things to consider.
What offices will we have?
Makeup of council
Method of casting votes
Determining result: simple majority? Different requirement based on type of vote?
Who gets a vote? One magus-one vote?
Are any special votes granted? Does anyone have the power to break ties?
Ownership of resources: who owns what
Payment of general upkeep
Maintenance of member labs
Maintenance of a guest lab
Magic item access
Different levels of membership?
Follow the Code of Hermes
Assist in fulfilling obligations to outside covenants (favors Flaw)
What else? Seasons of work for covenant?
What kind of vote does it require?
Do we have a low crimes/high crimes distinction?
I'm sure I've forgotten things. Feel free to add to the list.