Creating a cut line around objects not touching each other

Everything is possible. Automatic, live and editable.

But you give us far too little information! 

What do you really want? Please show a sketch or upload a sample file and post the link here.

Do you want only the outer cut line or also the inner one?
Do you want the cut lines to be rounded only on the outside or also on the inside?

If you mean to create a dieline that follows the shapes closely like this?..

The easiest way to do that is to select ALL objects (assuming they are vector), and apply a Path offset (Object > Path > Offset) setting a size of offset you want, as well as with Rounded joins. This will create a bunch of paths that you can then Unite into one shape with Pathfinder, and delete any odd shapes that might remain inside the main outside path. Then refine the shape as desired.

Best make a copy of all the art onto a separate layer to do this so there's no danger of screwing up your art.

Michael,

As I (mis)understand it, you can start out with an ellipse extending past and roughly following above My First and below Halloween, then add something suitable at the side and use Shape Builder or Pathfinder.

Which version of Illustrator are you using?

Also, I'm not sure exactly how the cutlines should look like. Can you provide sketches that may explain it better?

Sharing a sample Illustrator file would be helpful as well.