Relationships have nothing to do with the sheer number of connections to a database.
I am familiar with the basics of database design. I know when indexes are required, how to tune queries and such. If you are relying upon the "relationship" tool within access to optimize your database you are missing a lot of performance.
If you are going to be migrating your application into a pure SQL database with an Access front end then get completely out of Access (data wise) and forget the toys.