Currently it looks like you only have 2 choices for providing uniquessness validation for workspaces. You can key on a single field or you can key on the combination of 2 fields. It woud be nice if you had the option to combine more fields together for uniqueness.
For our Product Lifecycle Management, you must select a Product, Fiscal Year, Language, Product Release Type. These 4 combinations actually make our uniqueness key. It would be great if the "Unique Combination of 2 Fields in a Workspace" could be turned into 'Unique Combination of x Fields". (Possibly up to 6 different fields)