Nice, bright and clean, but perhaps somewhat static in its geometry. I suggest you look at the
rule of thirds or
golden ratio and see what you can do to unbalance the composition. Personally, I find that an unbalanced composition makes for a more dynamic display.
It might be as simple as taking the two plants you have along the sides and placing them together slightly off-center. If you can take the plants apart and make one taller than the other, even better.
I know this is a Rift lake tank, but google around for Amano style nature aquariums. Amano frequently has pictures of the tank with the hardscape set before he starts planting.
Blaise