This is going to look incredible when you finish it fifty. The progress you've already made is pretty astounding.

I've just got a couple of comments for you, before you go too far with the buildings:
--first, one of the biggest problems with city maps (in my experience) is remaining consistent with the scale. So far, I think you've kept the scale quite good, although perhaps some of your buildings are a bit too small.
--second, up close I think the texture on your docks looks a bit wrong. The way the lines all go the same direction, despite the shape of the dock is a problem, I think. Perhaps it would be better if you simply hand-draw the planks on a low opacity.
--I really like that the streets/public spaces seem to be defined by the buildings, rather than the other way around. That is something few city mappers do, and I wish more people would do, because it makes a closer match to historic city patterns (it also gives you those fantastic little alleys and squares that you're developing here). My only suggestion, at this point, is to not neglect the more obviously linear kinds of streets (i.e. the main roads that link different parts of the city, or the city to different parts of the world).
--I think there is a slight problem with some of your building roofs. It is especially the case with the buildings which have roofs that rise to a single point. From a construction/real-world point of view, that is not an efficient roof design, as it requires additional materials, less strength, and less drainage ability. (If you agree with my comment) I would suggest looking at satellite images of cities you are inspired by, and photos on Google Images, to get a sense of the many different shapes a roof can be.

All that said, I love the colours, love the textures, love the layout, really really looking forward to seeing this finished.

THW