Subscriber Ranking in the Consortium Environment

We want to start using ranking on the web for our subscribers, however we are a Consortium with lots of different discounts that depend upon:

-Which Consortium Org. the partron subscribes to

-What type of subscription the patron has within each Consortium.

We want to keep this as simple as possible...has anyone navigated the forest of Ranking in a Consortium environment? 

I would be very grateful to hear from you. 

-Becci Brace. TN Performing Arts Center.