Current thinking is not too far away from what you want but the trouble is how the restaurant is graded.
Current terms are :-
Essential Licences are granted as follows:
First grade establishments with a very good reputation - essential licences for Head Chef & Restaurant Manager issued for five years:
1. one renewable till permanent
2. the other with provision for one extension up to a maximum of seven years
Second grade restaurants with a lesser reputation or more restricted menu and new restaurants with a reasonably extensive menu - non renewable five year licences for head chef and restaurant manager
Third Grade, bar meal standard establishments - One non renewable five year licence for either Head Chef or the Manager
Other - No essential licence
The problem comes from the words "Grade", "Extensive" and Good reputation, whose to say what is what.
I think thought needs to be given to number of covers served - But does "X" get all the licences because he does 500 a night,
Financial Turnover - Try getting the figures to base that one on !!
Restaurant Grading - Don't work because most restaurants don't bother - there customers are the best critics !
It really is difficult to try and nail this down unlike hotels which have at least got a tourist board grading to work from - would such a thing work for restaurants / cafes ?