We'll start with the "downtown." It is slightly elevated...maybe 7 scale feet above track level, with a gradual incline rising from the area of the depot. Remember, this is the flat Texas coast, so any elevation change must be minimal to appear credible. And 7 scale feet is just enough to draw the eye upward from the tracks.
Another thing I've done, as the top photo shows, is to conceal the ends of streets that run into the backdrop. This done through angling the streets and blocking the view with trees and structures. This gives the impression that there's more "town" just out of sight.
(Above) The building to the left, Southern Maritime Supply, is situated midway along the long (12') section of the layout. It obstructs the view, in this case, to the north end of the layout, just as you'd encounter driving through an industrial area.
This is the area to the south of that building. Note the edge of "downtown" in the background. The roads in the industrial area do not visibly connect to the downtown streets, but are separated by multiple tracks. This lends the impression that there's much of the city of Gulf Harbor that can't be seen and that the port area is reached from a different section of the city.
Now we're looking from the other side of Southern Maritime Supply, with the view to the south partially blocked.
And this is what lies to the north of Southern Maritime Supply.
I used an odd corner on the north end of the layout to add a small scene. I leaned over the layout to get this shot; the edge of the backdrop at the end of the street shows in this photo, but is not normally visible to observers.
The roundhouse faces away from the room entrance, leading the observer to turn toward it and effectively making it a separate scene.