Electronic – Schematics for basic z80180 system

You should take a look at skidl which uses python to design and test a circuit and it will create the netlist https://github.com/xesscorp/skidl

I do not think there is good software for this. Most people use Visio or a clone. For example, here's a library of connectors for Visio. And you can change connector colors for different wire colors, add notes for sizes, etc. Otherwise I think there's not much - this is one of those million-dollar ideas that I stare in the face and ignore on a daily basis.