Sutekh

I like the idea of organic road building as well. Simply give each square a "road rating", and have different factors add and substract from this value. Stuff adding could be nearby cities and stuff like units and trade passing through. Once the value gets high enough a road is automatically constructed. Subtraction could be from bandit, enemies and monsters plus a small automatic amount each turn. The automatic substraction will ensure that roads not being used fall into disrepair and finall