Allow custom resize without config.php edit?

I would like to encourage others to use this plugin, but editing their config.php file may be too risky and technical. It would be nice if RIBU could have an option in its own settings panel, or else under the Media settings, to allow a custom resize target.

This is useful for when someone has “large” set to their content width, but may want a larger image to still be kept online for colorbox or zooms.

For example, one may prefer 720p-sized movie screenshots when someone clicks on the image, but they want the image in their post to display at “large” and only 640 × 360.

http://ww.wp.xz.cn/extend/plugins/resize-images-before-upload/