The arrangement on the left is PURE ART! Beautiful. It left needs to come more toward the center. Once the tank is planted you're going to loose it (which would be a SHAME) if you don't move it a good 3-4" toward the center.
What will your substrate be?
I would suggest going back to the rocks and getting some that are more uniform in color, or at least in the same tone family. It really pulls a scape together. Some on the right look to be more gold, and the one in the middle grouping with the wood- the really pale one - the rest look more taupe or ashy- that might just be the picture, but the ones I mentioned really stand out and that will damage the harmony of the tank. I think you have the size and relativity done beautifully, its just the color (on my monitor?) that pulls it apart. You don't want any one to stand out drastically from the rest, no matter how pretty it is.
You may want to have bigger stones if your foreground won't be sand, otherwise they're going to get lost. I really don't want to see those disappear, they are so pleasing. I can't wait to see the tank take shape, you have an excellent eye.
What will your substrate be?
I would suggest going back to the rocks and getting some that are more uniform in color, or at least in the same tone family. It really pulls a scape together. Some on the right look to be more gold, and the one in the middle grouping with the wood- the really pale one - the rest look more taupe or ashy- that might just be the picture, but the ones I mentioned really stand out and that will damage the harmony of the tank. I think you have the size and relativity done beautifully, its just the color (on my monitor?) that pulls it apart. You don't want any one to stand out drastically from the rest, no matter how pretty it is.
You may want to have bigger stones if your foreground won't be sand, otherwise they're going to get lost. I really don't want to see those disappear, they are so pleasing. I can't wait to see the tank take shape, you have an excellent eye.