Good start so far.. I agree with John about heavily planting and the leaf litter. A couple of ferns and some alocasia would look awesome in there. You've got lots of room to work with, so don't rush things... Don't forget that you can have a few epiphytic plants on the background as well.

Also, springtails and isopods are your friends... make sure you seed the tank with them, or springtails at least.