Setting up a large document with multiple duplicated objects and cut lines quickly in Illustrator.

Hello, I need to be able to set up multiples of the same image (periodically multiples of different images) in large documents that will be contour cut with a flatbed machine. The materials the images are printed on vary between 48x96 and 50x100 inches. The images will be linked from an original file. There is a special swatch set up so while I create the cutlines myself I only need to change the color to make it a cut line the machine can read.

I know how to do everything, I am just looking for ways to do it all quickly. I need to pump these files out as fast as possible, but I'm struggling on a proper workflow/strategy/what have you to do so. Sometimes images have their own cutlines with a 1/4" space between and sometimes images can share a cutline.

I have a coworker who has a few years more experience than I do who can seem to set up hundreds of images in no time flat, and I feel a disconnect on figuring out how to be as fast as they are. 

I have asked for help, but the way they are explaning things just isn't clicking with me, as if there's something that got left out that I'm just not knowing how to ask for. Yesterday they mentioned using the X and Y axis in the toolbars more but even then I don't know how that will make me faster.

I thought I knew Illustrator, but I guess not enough to be fast as I should be. I really could use all the help I can get. 

Please Let me know if I wasn't being clear describing everything.

Thank you!