Some nano rasboras in the Boraras family would look nice. They are an active schooling fish that is typically very small and do really well in nano tanks. You could have some nano shrimp. Or maybe a betta.
Are you willing to sell clippings of the plants? I had to ask since I am slowly trying to convert my 40g community tank into planted tanks and I am slowly setting up my 55g plan for planting. And you've got a great looking Kuhli Loach.