Transfer BI content from one project to another project

Hi Gurus,

we are planning to create something like a value added sandbox system and activate all standard business content and some common solutions, so the standard content and additional solutions can be ported over from this box to new projects in future .

1)If we activate the BI content and get in a transport request in sandbox and import this transport in a new project without activating the BI content again there?

2) Is there a better way to port over these solutions from one project to other project?

3) When we do this porting over will the datasources be a problem as the source systems will be different from the sand box and the new project?

4) Is there any common solutions that we can develop in BI that will be useful to be ported over to new projects?

Thanks in advance.