I'm making a masterplan for my new city the first time. Help!

Hi everyone I have always struggled with making cities aesthetically pleasing and functional at the same time. I always let my perfectionist me take over, and as a result I get a giant block of buildings, which isn't aesthetically pleasing nor functional.

I have decided I want to make a masterplan for my city and finally make something I am proud of.

First, I need to know if I am going to make my city in CS1 or 2. Keep in mind I really want to have detail in my city and mods are a must.

-I need a good map (preferrably a flat map)

-I need to have a program to plan my map on (Or a way to print the map and draw on it with a real pencil)

-I need a theme

-I will need mods (for example intersection marker, TM;PE and other must-have mods for making a very detailed city)

-I will need assets that have something to do with the theme

-A masterplan, ofcourse

-anything else?