Post more pics from different perspectives.

In your pictures, it appears that the W & D can't be moved to the other wall (left wall) because they would stick out too far. Is it possible to un-stack them and put them side by side on the same back wall? That way you could add shelves above and even a drying/hanging rack. The left wall could be used for shelves for storing laundry detergents, etc.

If the W&D fit unstacked on the back wall, I would do that. It will look better and give you more storage options. Here is our W&D next to each other on a back wall of a closet. As you can see, we were able to add storage above.

Those do not look good stacked on top of each other.

One thing to keep in mind about storage above the W&D is to not hang it so high that you can't reach it. I'm not able to reach the top shelf in my laundry closet so I put dry cleaning to be dropped off which we only do every month or two.