Thanks Craig for your response.
I actually don't want it to managed by a button on the field itself, that is just the functionality it has now, because it was the easiest and first thing I figured out how to do. I do have a method called generateSprite() that does most of that, except it's hooked into the wrong thing and isn't taking advance of the API as you mentioned above.
As for the configurations, it's more so users can determine the size of images, output location, nomenclature for the CSS that is outputted, etc.
And I agree with you about considering how and why I want sprites to be made. I can assume that a large percentage of the time, users will probably not need/want this module to create sprite sheets for normal layout purposes.
How this module came to be is that I am working on a site where the client wants a slider of images that build a collage. The slider has grid-like slides, where each slide is a 5x3 grid made up of 15 images. The images represent employees that work for that company. If there were 15 employees contributing a minimum of 5 photos each, that would be 75 images, or more importantly, 75 HTTP requests, just to build a 5 slide carousel. If the company and/or the amount of images per employee grew, so would the HTTP requests. So it made sense to me to take all those images and create a sprite sheet and which I can then just use one image to build out the carousel instead of 75.