Out of the box Dynamic Data over the Entity-Framework doesn't have the best support for large databases.
Note: This post will be a work in progress for a bit.
Avoid the EDMX designer
The designer surface will likely be cluttered to make sense of so stick to editing the XML by hand.
Generate the EDMX using EdmGen.exe or EdmGen2.exe at the command line.
StoreGeneratedPatterns to Identity on Primary Key properties
Dynamic Data Field Templates
Tables that contain a large number of rows and are referenced by a foreign key can be problematic as the default Dynamic Data implementation will create a drop down list to filter search pages.
Switching to alternative controls can resolve this issue.
Model Documentation and meta data