I have a website that will be used by people to store their business statistics and generate reports out of them. some of these are related rarely. these sets will be used rarely by multiple users. there were three designs that emerged 

1. use a single SQLDB and store all users data in the same and generate reports from there.
2. use one SQL CE db for each information set.
3. multiple SQL Server Databases one for the set

the application is in ASP.NET and will be hosted as public service. the traffic is expected to grow to thousands of information sets. 
please suggest best and alternates if any