Sub City Exploration: Redone

Reworked the city I worked on- the city the submarine was supposed to explore.  Here's the previous post of what the city looked like.  And here's what I've got so far.  I'm debating about coloring it with a limited color palette.

Ultimately I want to animate characters jumping off the roofs/ building walls in the foreground into the middle ground/ background.  

Progress: Scratch what I said before.  I'm being fickle and I'm changing my mind BACK to my original idea.  I want the sub to be exploring this underwater city.