Stamping and Cards are such a match made in heaven.
But who says your stamp has to stay on a single sheet of paper?
Stamp on two separate pieces of contrasting paper, and align cut out shapes on top of the original.
Lay a die cut sheet on top of your original and stamp through them both. Because of the thickness, of the dye cut, it's hard for the stamp to reach the surface right long the edges creating this outline.