Many thanks for all the input.
daniaw: smooth blue water might enhance the green spikiness of the moss, good idea. Unfortunately this was taken during a quick lunch break with no tripod or suitable rocks.
Wim: the new version here has a tiny rotation, but -- hey! -- mountainsides are not level.
Jeremy, Walt, Francois: I have further reduced the background mountains, and darkened them. Seems to perk up the moss a bit. I have other shots with less background that I'll work on.
Paulo: thanks!