The Black Diamond looks nice. As far as stock goes, that's a tough one. We all have different favorites.
Keep in mind that fish tend to stay in certain "layers" of the tank. For instance, in my tank the Rainbows always stay in the top 2/3. My Roseline sharks stay in the bottom 1/2. My Clown Loaches and Rams tend to stay in the bottom 1/3. With your tank being so tall, I would pay attention to the "layering" effect. You have a lot of space to fill, and don't want half the tank to look empty.
Or you might think about going with some fish that are tall? Altum Angels? Good luck and looking forward to seeing how it develops.