System Overview Database
The web reporting system database is central to report creation, data externalization, data integration and user administration - it will probably be the most important part of the project.
A web-based reporting system deals largely with signed out data, so it is not often updated (Reporting systems are more like data-warehouses than a transaction systems); therefore, normalization can be sacrificed for speed and clarity, if needed.
On the other hand, business rules should be implemented in the application layer, not the data model, especially if one is thinking about using the data for other purposes beyond reporting (vide infra).