There is one hidden thing that always creeps me out; below the tailor's, in a lavish basement room, you'll find a squad of captive leper gnomes laboring over mana looms. They are kept on track by a succubus, and you can see the fruits of their labor in the gold and jewels piled on the central desk.
You can also follow the Walk of Elders around and pass through a more impressive gate to reach the Royal Exchange. This courtyard houses the city's second Inn, bank, and auction house, and not much else. The Inn does allow passage to Murder Row, which has the potential to be heart-stoppingly awesome but falls short. Although it is home to the rogue/warlock headquarters, the windows visible above street level are shuttered and inaccessible.
A Study in Silvermoon picture series:
Walk of Elders, The Royal Exchange
Murder Row, Farstrider's Square
Court of the Sun