Maps often use lines with different colour and pattern edges - eg, a red fill with solid black edges for a highway, red with one solid and one dotted for a secondary road, etc; blue with dark blue for a major river, blue with no border for a dry or seasonal river.
Assuming no one has created one already (I did search!), how easy would it be for a technical person to create such a tool? I am picturing options for width; fill and edge colours; edge styles.
Would anyone be willing to take on the task, as I am not such a technical person?