Ben you can use black wall paint instead of shoe polish. Just thin it out a tiny bit with water in a plastic cup & use a sponge brush to wipe it on & really drag it out with your brush but don't fill your brush too full with paint. Experiment on some cardboard to find the right effect, also try sponges etc till you get it the way you want & then have at it with your walls!! Also check out HGTV online shows for ideas & more effects for painting. You could also paint 1 (focal wall) red for contrast. I love to decorate & have tons of ideas. Definitely make your bedding stand out too. That would be another great place to add red without painting any walls
If you are artistic you could do a few paintings, even a skull & crossbones etc. if you want more ideas you are welcome to PM me & have fun!!