I tested the principle of the row houses and I believe it would work. It didn't go quite right because I found it impossible to accurately edit the huge rows of hex where I should have deleted two chunks of bytes on every line over several files. It's not realistic to do that manually, so I hope shrinking will be included in the lot expander.
Anyway I got a lot 11 lot-tiles wide (I meant to make it 10) and unfortunately I deleted the left hand 19 rather than the left 10 and the right 10 as I had intended. Again something including it in the program would easily help with.
I started by building a simple square building on the centre 10 tiles of a 3x2 lot. The walls remained standing on the edge of the lot and therefore could be used as the party walls of a row house.
"You can do refraction by raymarching through the depth buffer" (c. Reddeyfish 2017)