Really like your fish!!!
I have many suggestions:
1) It definately is easier to clean with a bare bottom, but it looks quite ugly, fish will prefer the gravel, the gravel will also hold some good bacteria which will help keep your tank more stable.
2) Add live or fake plants to make it more interesting for the fish and more visually appealing.
3) Get a Black background, it will show up your fish much better than a picture, but thats personal preferance.
4) Fill the water up to the top!!!! Why is it only half full? This is a huge waste of space!! 2 inches from the top is a good size.
5) Rocks, bogwood and driftwood! Get rocks and natural decoration! It will make the tank look wayyy better.
Otherwise, really nice spacious tank! Lovely fish!!