I personally really love this one. Especially the first picture on this page, I like how the floaters look like a cloud!
I would maybe move the red bush-looking plant (sorry I've never seen one like it before, don't know what it's called) back a little bit since it's bigger than most other things in the front, but that's just me.
I would also maybe replace the fissidens as it does look a bit yellow, but maybe it's just the lighting like you said. Maybe a few longer stems or grasses in the back to give it more depth since some of the slope you had at first seems to be lost a bit in the plant growth.
But I really love the look of it as a whole. It's definitely one of my favorite scapes, I'm just offering my nit-picky art kid opinion lol.
Also I would love ot know what that red plant is, it's gorgeous.