I've always had box build rather than an off-set build, but it depends on the quest/map. Generally though, I have my layout as such: Warriors guild directly in front of castle, Ranges on the right of warriors, Rogues to the left of warriors. Marketplace on the left or right side, blacksmith on the opposite. Wizards behind the blacksmith, Cleric behind the market, and the Bazaar behind the castle.

This is assuming there is room for them, but that's my general layout. Elves are built next to the Market, Dwarves next to the blacksmith. Guard towers are built based on the quest/map for effectiveness against waves of enemies and/or monster lair. I'd rather let the heroes deal with the sewers and graveyard to give them money to continue buying things and leveling up.