Over the last two years I have extended my open source image manager that searches for unused images. Especially I have improved the speed and performance, so that it can handle much more data than the old version. I call it the "Image Upload manager Pro".
When using it for my entire database I saved about 150 MB from 600 MB, 25 % less space in the database.
Here is a preview:
You can also separately delete files and this is also new, you can rotate JPG images:
I think for the long dev period I will take a symbolic fee of 9 USD for everyone who likes to get it. In case someone does not want to spend any money, you can still use the free version.
The plugin is not released yet.