I wouldn't bother with the 18-35 on a crop body sensor, you may as well just use the kit lens (also, on full frame it has some pretty weird distortion, not sure about cropped but can see them slightly in those pics).
I'll be honest, I really wouldn't want to go much wider than 18mm for group shots as you're in danger of just making people look wiiiiiiiiide, which they'll not thank you for.
However, if you want a wide angle lens that will autofocus on your camera then I think you're limited to the Nikon 10-24 or the Sigma or Tamron equivalents. There are others such as the Sigma 12-24 which is very good but not sure if it has an inbuilt autofocus motor.