The reason not to use Exporter would be to easily identify which module contains the body of the subroutine that you are calling. If you create many modules and then export them all into the same namespace it might get confusing about which subroutine belongs with which module. Also, it helps to avoid the case of two modules exporting a subroutine with the same name. Just something to keep in the back of your mind as you develop the code.

As far as the object goes, I think you have a good grasp of what an object is. For a package to define an object, it must contain a subroutine that returns the blessed reference. This is typically named "new" but it does not have to be.

I may have caused some confusion by using the terms module and package interchangeably - which they are (for the most part) in my own mind. I am not sure of what the actual difference between the terms is though.