I like what you are doing with the map. The road network strikes me first as being well done. It looks like the inner ring was the old city and possibly had the old city walls, but were eventually taken down in favor of the current placement of the walls (much like Wall St in Manhattan). Then the other streets branch off of the main thoroughfares in a haphazard/organic fashion, it really gives the look of the organic evolution of a settlement.
If you are concerned at all about scale, I dont think you should be. If you keep the scale of the buildings you have in the South, I think it will make the (what I assume to be) warehouse district to the north of the city look to scale.
I look forward to watching this one progress