Very interesting. All this seems to fit with my own research, focusing on New World travel during the 17th-19th Centuries, mainly horse and foot travel.

Something else to bear in mind is weather. Rain-swollen streams, mud and muck, fallen trees due to wind and rain, snow, sleet, etc. Don't assume every day will be fair, sunny, and warm. People tend to travel through regions when the season is most cooperative, and water, food, and shelter most plentiful. In hot climes, the cooler seasons. In wet climes, the dry season. And in cold places, the summer. Prior to the late 19th Century, when you must travel "out of season," you were taking chances with your schedule, and your cargo, if not your life.