Hey thanks.
I actually used one of your previous edits as a reference to try and improve the 'big bricks' this time.
You're right though, they could definitely be more irregular.
About the railing, it gets cut off because of the way it tiles. But yeah, I'm pretty dissatisfied with the way it turned out. I might get rid of the whole thing and try a simpler design.
Edit: Oh I think you were referring to the big brick getting cut off. This is a tiling issue as well : (
In regards to structure, I present to you my reference photograph: