I've noticed that there are no settings for default 'Image Cleaning option'.
There should be settings for that. Otherwise, if I want a document to be grayscale on all pages I've to change the cleaning option for all the pages one by one.
There's another suggestion,
When changing the cleaning option for one page, long pressing on the option should provide with a menu to change the cleaning option for 'All pages' and 'All following pages'
Thanks for sharing your findings. We appreciate your feedback and efforts on this.
You may share your views by filling the feature request form Scan Android Feature Request and Bug Report Form.
the concern team will review the same.