Stunning! Very pleasing to the eye, and nicely done. Gives new meaning to "airplants". I really like the idea of no fauna, only flora (along with not having to monitor water quality or do water changes).
What type of maintenance tasks are you having to perform? Do you fertilize your plants? What substrate are you using? Are you keeping your set-up @ room temperatures? Will you continue using the plastic on top of the tank if you decide to keep it emersed? Your idea seems like it will evolve into a very interesting long-term project.