“Edit Image”: predefined aspect ratios and copy original image (not overwrite)

Hello there,

I’ve got two main questions:

1)
When editing an image (crop/rotate screen), the user can type in an aspect ratio and the “crop” selection on the image will have that fixed aspect ratio then. Now, I’d like to know if it is possible to have a predefined select-list of aspect ratios, so you don’t have to memorize website-relevant aspect ratios but can instead just pick one and it will automatically fill the values.
Is that a) configurable in WordPress or b) is there a hook available where I might write my select list in (plus some javascript)?

2)
When cropping and saving an image, WordPress will write a new file (new filename) and keep the old (original) one, but won’t show the original file in the media list). Is there a way to give the user the option: if he wants to overwrite the original image in the media list (current behavior) or duplicate the original image in the media list, so both the original image and the cropped image are their own thing in WordPress?

Thank you for your input!