Those on the left side of the theater (as you're facing the stage) did indeed have their view obstructed by home base. They could see the program feed on the monitors, but not much else. Most of the time, half of the rows in that section were covered by black duvetine, and the rest of the section would seat the contestants' guests (so as to prevent the contestants from looking out into the audience for signals).
The bonus area was indeed pretty much where you imagined it, except it was probably about 10 feet or so away from the edge of the stage.
