Hi Community,
We actually do offer a feature like the one you described on the new version of the Saved Listings page that we have been working on recently and you can reach that page by clicking the “Try out our new and improved Saved Listings page!" link near the top of the standard Saved Listings page.
If you use the “Delete” button to remove one or more listings from the new Saved Listings page, you should be presented with an option called “Also delete images associated with these ads” in the confirmation window that you can check if you would like to delete the images in the listing(s) as well.
We are currently planning on making the new version of the Saved Listings page the default version of that page with a future site update but, for now, it will require an extra click to get there from the standard version of that page.
I hope this helps. If you need any further assistance with your account, please feel free to contact our customer support team by mousing over the “Help” tab within your account and selecting the “File Support Case” option.
-Mike