I am addressing the template "image" issue in particular - in v3.6.1.
The new version allows multiple simultaneous selections (yahoo!).
So an idea would be to name your template items with a prefix that guarantees they will all appear in one alphabetical sequence... e.g. "tempImage01_house", "tempImage02_magazine", etc.
In the Resources Panel, at the top, select "Images" from the drop down menu filter.
You can then do a standard shift click at the top & bottom of the alphabetized "tempImage" list and hit delete. Should take about 5 seconds to accomplish.