Adobe Illustrator has a trace shapes tool which might be useful. (It gets awfully messy if you use it on sketches, but for maps that are already crisp and clean and you are more trying to get contours, it might work. (Or you can use it to trace a large section of drawn borders, and then use the traced bit to subtract shapes from, and re-add them back together.)

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Er. I'm still pretty new, so I don't know what the rules are about world building feedback versus the strict cartographic stuff, so please let me know if this is not kosher, but since part of the study of geography includes that of political borders, I'm gonna message you some personal feedback, take it for what you will. (Otherwise, are there rules about tangential feedback? )