I like the background, but the natural scene conflicts with the what's in the tank. If you can find a background that isn't natural looking, it might add to the uniqueness of the tank. With an air pump, you can add a few bubble features.
With most people going for the natural look in their tanks, yours is by far one of the more unique tanks I've seen here and stand out as very original. With a little more imagination, it's could become a surrealist nightmare.
There are many pluses. With the artificial plants, and a near empty tank, you can move things at will without causing death or killing the roots. I've killed many plants trying to have an aquarium that is also an erector play set. I'd love to be able to rearrange my tank every 2-3 weeks and have a different look when ever I wanted.