Cool story man, you can really see how your knowledge is growing and you're getting better and better. I like a couple of the stone layouts. The crane one was neat. The last could be really good, you just need to adjust it. It looks like the two rocks pointing left need different angles.
Nice work taking your time and going through it over and over. Keep in mind though, that the scape looks rather different with soil and you aren't using slope to your advantage in the earlier scapes. I do see you have a few books or something to create some height in the new layouts. You may want to get some dry AS in there and play with slops and such before you decide which particular layout to move forward with. The crane layout could be more dramatic with a mound, as well as the last layout there. The concave would look completely different with a valley, or a mound.
Try it out.
I totally agree
I am using 1" foam insulation (had a bunch lying around) to stack under the towel to give it height and stabilize the bigger stones. It works pretty well. I'll probably use it in the tank too, since AS is so light, with big stones it tends to just slide around. When the tank shows up I"ll see how it goes. I'll also add more height, as I have plenty of vertical space to play with.