I grow them, but my aquascaping skills are lousy. The Heteranthera zosterifolia can be used as a background plant, I might suggest moving the Bacopa monnieri to the Dipilis diandra position, and put the H.z. in that back corner. In the old H.z. spot put a grassy crypt, you are missing the vertical line contrasts in your layout, Crypt. albida or C spiralis, or C. retrospiralis might make the contrast.
Heck I might move the Ludwigia inclinata to that spot and put C balansae back there but you have an Aponogeton boivinanus back there which the balansae would clash with.
Or you could just fill in the old H.z. spot with the Lobelia, it is a good plant for establishing a slope with, and it is one you recommended which gives it a leg up on everyone else since this is your tank and it is for your enjoyment.
Aquascape? I'm a crypt farmer.
It's a fine line between fishing and standing on the shore looking like an idiot.
That IS an aquascape, it's titled "The Vacant Lot".