Damaged photos are not a lost cause. You can augment them by adding embellishments, washes, mark making, stitching, sketching, colouring, or other alterations to bump their visual interest.

You can also try a more abstract or collage-like technique where you cut away parts of an image to reveal something underneath, or to leave a blank space.

Consider trying the above with a black and white photo perhaps, where you cut parts away to reveal colours underneath. You can achieve this by layering cut photos on top of each other, by colouring in with pencils or markers, or by layering the cut photos on top of patterned paper.