I have that exact tank set up as a shrimp bowl and planted! Small world. :)
I ended up painting the back dark because it was so distracting seeing everythig behind it. I think I even have similar gravel. I tied the moss to a piece of fake driftwood I picked up at the petstore to look like a little tree, then have some crytocoryne wendetii along one side. They only get to 4"-6" tall. After the picture was taken, I attached an anubias nana petite to the tree. The shrimp love having all of the things to climb on and pick through. I'll try to get a current picture so you can see how the crypts have grown in.