Found a neat program called Mischief, the most interesting feature to me is the infinite Canvas, you can zoom in an infinite number of times, or zoom out.. so you could draw a building, add buildings, zoom out, add county lines, zoom out, add country lines, continents, and so on forever, you can export sections to photoshop layers, it has layers and pins so you can landmark places in your drawing.

It's $25 bucks for the paid version which gives features like layers, export to PSD and so forth. Example video here:
https://video-sea1-1.xx.fbcdn.net/hv...93&oe=558B6841

Home page is here:
https://www.madewithmischief.com/

If nothing else this looks like a really good tool to rough out maps up to world scale and then export bits of it to another program where you might have better filters or other tools..