This sounds like an interesting idea that has scope beyond the legal profession and into areas such as shared service management (where you might need multiple levels of management to review, edit, sign-off a comms before sending).
An 'approval to send' option might also help here.
There are lots of possibilities for sure, and some customers have also asked about this. Getting somebody to help with the development work will greatly assist in being able to better explore these opportunities.
Best of luck with your search. I'm not the candidate you are looking for but something about your product description makes that nice 'click' noise in my brain.
An 'approval to send' option might also help here.