Looks nice! I like the massive development you've got here. Just some tips to improve it further. Maybe it would look better if you use underpasses at the highways instead of bridges. If you use bridges it might be worth thinking about a sunken highway. There are really cool walls you could use. I'm using there are other downloads of these same walls, I would recommend to download them as well.
Thanks for the Tips! I wish i would know someone in my Homearea, to show me all the "sim secrets" At the moment it is not so easy....