Optimize images on file upload

I'm a new user of this module for D8 and I've set up a few image styles to use a resmush.it pipeline with the 2016-Oct-05 dev version, which seem to work, although I'm not seeing a huge difference in resulting filesizes between resmush.it and the imagick library I was using.

I was primarily interested in optimizing the filesize of the "original" image upon uploading (this is typically where we can save most space), but I do not see any significant optimization happening there and I can't find a way to set a pipeline for this image size, since there is no original style... I was expecting to find something on /admin/config/media/image-toolkit or on the admin content-type field form where a max resolution can be set, but I haven't found it. Did I miss anything?