We can't report on unallocated resources which is a huge staffing problem for us. We want to be able to pull a report of resources that are not allocated to a project so that know who is available and put them on a project. I can't believe this isn't in the system.
As discussed with you, you can run a Project Team Assignment Template provides you with the details on all the users added within the project team section and the corresponding allocated hours. For all the users that haven't been allocated, the report will show you a null value.