I love that medieval city generator! I started using it last NaNo. I’m never completely satisfied with the results because I generally already have an idea in mind for my cities, so I take one of those maps from the generator and export them. I then import it into Adobe Illustrator and change/grow them to fit my needs. The map for the capital city in my fantasy novel is pretty detailed now with farms, an aquaduct, wells and public fountains, etc. It’s a lot of fun!
For maps of countries/the world, I always used to draw them by hand. Now I use Photoshop an just free-form everything until I get something that I like. I downloaded a brush set for the mountains and trees to make them look a little nicer. I may redo them all this year as part of NaNo prep. There are a ton of great step-by-step tutorials on YouTube for creating fantasy maps.
EDIT: I am now adding a map I did last year of Shehlon in Illustrator. It’s messy, and I’ll likely redo it this year during prep. But, you can see the various buildings and tiers of the city, as well as the aqueduct in orange.