I always follow a contained user model when setting up users within my Azure SQL Database. I do this so the user in question has access to only specific database(s) and does not have a login to the server. It becomes even more apparent the importance of this when you design a solution based on failover groups.
When a failover occurs to the secondary, I want a pleasant experience for the user. With the contained user model, the user goes with the database. I don’t want to do admin work on the new primary (post failover). Let’s see.