Hi, I Like the setup but agree that the ones on the left look a little wrong, maybe try having the bigger middle one (second from the front) sticking forward and the back one vertical behind it for more height? I can't tell the scale but it lookings like you would need only carpetting plants or else you would cover the rocks on the right.
Also banking with cat litter doesn't last well in my tank as its so light the water movement flattens it quickly so you might need to have something in the substrate to hold the banks in place.