For accessibility and usability, there must be more than one way to interact with elements on the page. Generally, this is the keyboard and/or a screen reader. The Image Sequencing content type is completely inaccessible because the images cannot be reordered without the mouse. The screen reader is unable to select a single element and then move it. The information that would need to be conveyed:
The total number of images
The alt text for each image
The image's current place in the order of images
The image's new place after being moved.
The Drag and Drop content type works without a mouse, so perhaps the logic behind that content type could be adapted to work for Image Sequencing.