IDEA lets me move sources around in a simple way: select the class/interface/enum and do a Refactor -> Move. It will give a nice little dialog to select a new package. This dialog also has completion. Perfect. Also works for moving multiple items in one batch.
Now enter classpath resources like images, xml files, property files, whatever. Instead of the dialog where you can so easily choose the target package you now get a 'Move file' dialog. This dialog then allows you to move things around in a filesystem manner, showing raw directories instead of packages. And also without completion. This is cumbersome to use.
In my opinion it makes sense to have the first dialog to move classpath resources around. Since these items are all in a folder marked as 'source code' why not treat them all the same?
Another problem that would be solved then is the fact that you cannot select both a Java source file and a non-source classpath resource in the same package and then move them to a new package together. Right now when you do that IDEA completely disables the Move refactoring option and you have to do seperate 'Move' and 'Move file' actions.