That looks superb, the sense of depth is awesome - something that's very hard to achieve. Your plant choice is good too, i recon it's gonna look brilliant.
Moss stones around the path will help greatly with softening. I'd suggest using something like the substrate supplied with a Biorb, i've had great success with it before. I wouldn't go buy them though, I only used some since I had them lying around. I do tend to think that rough stones are the future for moss, not really pebbles as I feel that the the moss finds it harder to attach it's self to a smooth surface.
Love it!