A simple workflow to resize selected images to a predifined resizing ratio (10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%).
Resize (+Tab)
Then a list of resizing ratio will be proposed. Just choose what you want the hit "RETURN".
if you want to keep a copy of the selected resized images, pres "CTRL"
The workflow is about 14Mo of size. This is due to a very quick and dirty approache of using an automator function for each ratio of resize. Each automator binary is about 1,7 Mo. You can create you own by creating an automator applictaion that take photo and apply a resize per percentage.