Well since the world is a massive labyrinth you literally could not map out without the use of electronics and 3D super computer shizwah but we're always gonna need ideas for quests throughout the story. 

As for towns I have nothing much in mind yet, the only idea I had was one town for each class sort of like a slight industrial port town city of thieves/pirates, a elven-esque city in the forest, a massive medieval city dominated by a castle and powerful knight guards, a magical mage town of.. magic and maybe a fifth level for beginners since all games have that even ground starting point? So if you had ideas on towns please share.